{"id":18304,"date":"2026-10-30T05:54:43","date_gmt":"2026-10-30T11:54:43","guid":{"rendered":"https:\/\/www.supportpro.com\/blog\/?p=18304"},"modified":"2026-10-30T05:55:11","modified_gmt":"2026-10-30T11:55:11","slug":"amazon-linux-2-efs-utils-update-cve-2026-15957","status":"publish","type":"post","link":"https:\/\/www.supportpro.com\/blog\/amazon-linux-2-efs-utils-update-cve-2026-15957\/","title":{"rendered":"CVE-2026-15957: Is Your Amazon Linux 2 Server Affected?"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">Linux administrators must keep more than the operating system kernel up to date. Supporting packages that handle storage, networking, and cloud integrations also need regular maintenance.On October 28, 2026, AWS released security advisory <strong>ALAS2-2026-4044<\/strong> for <strong>CVE-2026-15957<\/strong>, a vulnerability affecting the <code>amazon-efs-utils<\/code> package on Amazon Linux 2. AWS classifies the advisory as Important and identifies <code>amazon-efs-utils-3.1.3-1.amzn2<\/code> as the corrected package.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The vulnerability involves uncontrolled recursion in Smithy-RS-generated deserialization functions. Deeply nested data can exhaust the stack and cause a process to abort, creating a <strong>denial-of-service (DoS) risk<\/strong>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Administrators should identify affected instances, update the package, and verify that applications using Amazon Elastic File System (EFS) continue to work.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">What Is the Amazon Linux 2 EFS Utilities Update?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The <code><strong>amazon-efs-utils<\/strong><\/code> <strong>package<\/strong> provides utilities that help Linux instances connect to and use Amazon EFS. Applications use EFS to access shared file storage across supported workloads.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">AWS released <strong>ALAS2-2026-4044<\/strong> to address CVE-2026-15957 in this package.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Here are the key advisory details:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Advisory:<\/strong> ALAS2-2026-4044<\/li>\n\n\n\n<li><strong>Advisory release date:<\/strong> October 28, 2026<\/li>\n\n\n\n<li><strong>Affected package:<\/strong> <code>amazon-efs-utils<\/code><\/li>\n\n\n\n<li><strong>Vulnerability:<\/strong> CVE-2026-15957<\/li>\n\n\n\n<li><strong>AWS severity:<\/strong> Important<\/li>\n\n\n\n<li><strong>Fixed package:<\/strong> <code>amazon-efs-utils-3.1.3-1.amzn2<\/code><\/li>\n\n\n\n<li><strong>Supported architectures:<\/strong> x86_64 and ARM64 (aarch64)<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Administrators can review the official AWS Amazon Linux 2 security advisory for package details and remediation instructions.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h2 class=\"wp-block-heading\">What Is CVE-2026-15957 and How Can It Affect Linux Systems?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>CVE-2026-15957<\/strong> affects deserialization functions generated by Smithy-RS, a Rust code generation and runtime framework used by the AWS SDK for Rust and custom service implementations. The affected functions process JSON, CBOR, and XML data. When they handle deeply nested data associated with a recursive model, uncontrolled recursion can consume excessive stack space.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">An attacker may trigger this condition in a reachable vulnerable component, causing stack exhaustion and a process abort. This creates a <strong>denial-of-service risk<\/strong>. The vulnerability does not directly indicate data theft or unauthorized data modification. Its main concern is service availability.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For infrastructure teams, a process failure can interrupt services that depend on the affected component. The actual impact depends on how the vulnerable functionality operates within the environment.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">AWS identifies <code>amazon-efs-utils<\/code> as the affected Amazon Linux 2 package. However, administrators should not assume that every EFS mount is directly exploitable or that every existing mount will fail. They should update the package and test the applications that rely on EFS.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Tenable also provides a <a href=\"https:\/\/www.tenable.com\/plugins\/nessus\/373428\">Nessus plugin for ALAS2-2026-4044<\/a>. It checks whether a system runs an affected package version. Note that Tenable classifies the finding differently from AWS, so teams should follow their own vulnerability assessment and prioritization process.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For a broader understanding of how critical vulnerabilities affect infrastructure, see SupportPRO&#8217;s article on <a href=\"https:\/\/www.supportpro.com\/blog\/top-infrastructure-security-lessons-from-recent-critical-cves\/\" target=\"_blank\" rel=\"noopener\">infrastructure security lessons from recent critical CVEs<\/a>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h2 class=\"wp-block-heading\">How to Check Whether Amazon Linux 2 Hosts Are Affected?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Start by checking which instances have <code>amazon-efs-utils<\/code> installed and whether they run the corrected version.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">1. Check the installed package version<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Connect to the Amazon Linux 2 instance and run:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>rpm -q amazon-efs-utils<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">Compare the output with the fixed version, <code>3.1.3-1.amzn2<\/code>. Package versions earlier than this release are affected by the advisory.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For multiple instances, use configuration management, system inventory, or vulnerability scanning tools to identify affected hosts across your environment.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">When a new CVE appears, teams should first establish which systems run the affected software and prioritize remediation. SupportPRO explains this process in its article on <a href=\"https:\/\/www.supportpro.com\/blog\/how-to-assess-whether-a-newly-published-cve-affects-your-servers\/\" target=\"_blank\" rel=\"noopener\">assessing whether a newly published CVE affects your servers<\/a>.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">2. Check for the advisory update<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Run the following command to review the advisory-specific update information:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>sudo yum updateinfo info ALAS2-2026-4044<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">The result depends on repository configuration and available metadata. If the command does not return the expected information, check repository connectivity and metadata before deciding that the host is unaffected.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">3. Identify EFS-dependent workloads<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Prioritize production instances that use EFS for shared application files, uploads, content directories, or persistent data.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Record each affected instance, its installed package version, and the applications that depend on EFS. This inventory helps teams plan updates without overlooking less frequently accessed workloads.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">How to Fix CVE-2026-15957 on Amazon Linux 2<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">AWS provides two update commands for this advisory.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Option 1: Update only the EFS utilities package<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>sudo yum update amazon-efs-utils<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Option 2: Apply the advisory-specific update<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>sudo yum update --advisory ALAS2-2026-4044<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">Choose the command that fits your patch management process. The package-specific command targets <code>amazon-efs-utils<\/code>, while the advisory-based command applies the update associated with the security bulletin.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Before updating production systems, review the package transaction and follow your change management process. Hosting providers and infrastructure teams should test the update on a representative instance before rolling it out across their server fleet.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For another example of why timely Linux patching matters, see SupportPRO&#8217;s article on <a href=\"https:\/\/www.supportpro.com\/blog\/ghostlock-cve-2026-43499-how-to-protect-your-linux-servers-from-the-latest-kernel-vulnerability\/\">patching Linux servers against known vulnerabilities<\/a>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">After installation, confirm the package version:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>rpm -q amazon-efs-utils<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">The output should show <code>3.1.3-1.amzn2<\/code> or a later applicable fixed release.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">If the update fails, check repository access, package dependencies, and the package manager&#8217;s error messages. Do not treat a command&#8217;s execution as proof that the update succeeded.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h2 class=\"wp-block-heading\">What Should You Check After Updating EFS Utilities?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Installing the patch does not complete the remediation process. You must also verify that EFS-dependent applications continue to work.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>1. Check EFS mount status<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Run:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>findmnt -t nfs4<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">Amazon EFS commonly uses NFSv4.1 for Linux mounts. Confirm that the expected mount points appear in the output.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>2. Test application access<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Check whether applications can read and write to their EFS directories. Use the correct service accounts and permissions during testing. A successful mount does not automatically confirm that every application has the required access.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>3. Review system and application logs<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Look for mount failures, permission errors, unexpected process exits, and other issues that appeared after the update.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>4. Monitor dependent workloads<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Check application health, request failures, background jobs, and services that rely on shared EFS storage. Compare their performance with the expected baseline and investigate unusual changes.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>5. Record the remediation<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Document the affected hosts, previous and updated package versions, maintenance window, and validation results. These records help teams track patch compliance and support internal reviews.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Amazon Linux 2 End of Support: What Administrators Should Consider<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">AWS identifies Amazon Linux 2 as an <strong>end-of-support (EOS) operating system<\/strong> in the ALAS2-2026-4044 advisory.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Organizations that still run Amazon Linux 2 should address available package updates while planning their move to a supported operating system. Applying individual patches does not replace the need to assess the risks of running an EOS platform.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Hosting providers and managed service providers should:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Maintain an inventory of Amazon Linux 2 instances.<\/li>\n\n\n\n<li>Track applicable AWS security advisories.<\/li>\n\n\n\n<li>Identify applications and services that depend on legacy instances.<\/li>\n\n\n\n<li>Check package and EFS compatibility before migration.<\/li>\n\n\n\n<li>Plan migration to a supported operating system.<\/li>\n\n\n\n<li>Automate package inventory and vulnerability checks where possible.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">A consistent patching and validation process helps teams manage vulnerabilities across multiple servers. SupportPRO&#8217;s <a href=\"https:\/\/www.supportpro.com\/blog\/how-to-build-an-enterprise-vulnerability-management-program-for-linux-servers\/\">Linux server vulnerability management approach<\/a> covers the wider process of identifying, prioritizing, and addressing risks across Linux environments.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Conclusion<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">AWS advisory <strong>ALAS2-2026-4044<\/strong> addresses <strong>CVE-2026-15957<\/strong> in the Amazon Linux 2 <code>amazon-efs-utils<\/code> package. The vulnerability can cause a denial of service through uncontrolled recursion, and AWS identifies <code>amazon-efs-utils-3.1.3-1.amzn2<\/code> as the corrected release.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Administrators should check package versions, identify affected instances, apply the update, and test EFS-dependent applications. They should also include Amazon Linux 2&#8217;s end-of-support status in their operating system migration plans.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Managing these tasks across a large server fleet takes consistent monitoring and patch management. SupportPRO provides <a href=\"https:\/\/www.supportpro.com\/aws_management.php\" target=\"_blank\" rel=\"noopener\">AWS infrastructure management services<\/a> to help businesses maintain their infrastructure, apply updates, and monitor server health.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Frequently Asked Questions<\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">1. What is ALAS2-2026-4044?<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">ALAS2-2026-4044 is an AWS security advisory released on October 28, 2026. It addresses CVE-2026-15957 in the <code>amazon-efs-utils<\/code> package on Amazon Linux 2.<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">2. What is the fixed version of amazon-efs-utils?<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">AWS identifies <code>amazon-efs-utils-3.1.3-1.amzn2<\/code> as the corrected package. Administrators can check their installed version with <code>rpm -q amazon-efs-utils<\/code>.<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">3. How do I fix CVE-2026-15957 on Amazon Linux 2?<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">Run <code>sudo yum update amazon-efs-utils<\/code> or <code>sudo yum update --advisory ALAS2-2026-4044<\/code>. Confirm the installed package version after the update.<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">4. What is the impact of CVE-2026-15957?<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">The vulnerability can cause stack exhaustion and terminate a vulnerable process. This creates a denial-of-service risk that can affect service availability.<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">5. Does CVE-2026-15957 affect every Amazon EFS mount?<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">The advisory identifies <code>amazon-efs-utils<\/code> as the affected package. It does not establish that every EFS mount is directly exploitable or will fail. Administrators should check package versions and test dependent applications.<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">6. Is Amazon Linux 2 still supported?<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">AWS identifies Amazon Linux 2 as an end-of-support operating system in the advisory. Organizations that continue to run it should apply available updates and plan migration to a supported platform.<\/p>\n\n\n\n<div class=\"wp-block-media-text alignwide has-media-on-the-right is-stacked-on-mobile is-vertically-aligned-center has-white-background-color has-background\"><div class=\"wp-block-media-text__content\">\n<p class=\"has-large-font-size wp-block-paragraph\">Facing issues? <\/p>\n\n\n\n<p class=\"has-large-font-size wp-block-paragraph\">Our technical support<br>engineers can solve it. <\/p>\n\n\n\n<!--HubSpot Call-to-Action Code --><span class=\"hs-cta-wrapper\" id=\"hs-cta-wrapper-3350a795-db50-482f-9911-301930d1b1be\"><span class=\"hs-cta-node hs-cta-3350a795-db50-482f-9911-301930d1b1be\" id=\"hs-cta-3350a795-db50-482f-9911-301930d1b1be\"><!--[if lte IE 8]><div id=\"hs-cta-ie-element\"><\/div><![endif]--><a href=\"https:\/\/cta-redirect.hubspot.com\/cta\/redirect\/2725694\/3350a795-db50-482f-9911-301930d1b1be\" ><img decoding=\"async\" class=\"hs-cta-img\" id=\"hs-cta-img-3350a795-db50-482f-9911-301930d1b1be\" style=\"border-width:0px;\" src=\"https:\/\/no-cache.hubspot.com\/cta\/default\/2725694\/3350a795-db50-482f-9911-301930d1b1be.png\"  alt=\"Contact Us today!\"\/><\/a><\/span><script charset=\"utf-8\" src=\"https:\/\/js.hscta.net\/cta\/current.js\"><\/script><script type=\"text\/javascript\"> hbspt.cta.load(2725694, '3350a795-db50-482f-9911-301930d1b1be', {\"useNewLoader\":\"true\",\"region\":\"na1\"}); <\/script><\/span><!-- end HubSpot Call-to-Action Code -->\n<\/div><figure class=\"wp-block-media-text__media\"><img fetchpriority=\"high\" decoding=\"async\" width=\"904\" height=\"931\" src=\"https:\/\/www.supportpro.com\/blog\/wp-content\/uploads\/2022\/09\/Free-server-checkup.png\" alt=\"guy server checkup\" class=\"wp-image-12943 size-full\" srcset=\"https:\/\/www.supportpro.com\/blog\/wp-content\/uploads\/2022\/09\/Free-server-checkup.png 904w, https:\/\/www.supportpro.com\/blog\/wp-content\/uploads\/2022\/09\/Free-server-checkup-291x300.png 291w, https:\/\/www.supportpro.com\/blog\/wp-content\/uploads\/2022\/09\/Free-server-checkup-768x791.png 768w, https:\/\/www.supportpro.com\/blog\/wp-content\/uploads\/2022\/09\/Free-server-checkup-585x602.png 585w\" sizes=\"(max-width: 904px) 100vw, 904px\" \/><\/figure><\/div>\n","protected":false},"excerpt":{"rendered":"<p>Linux administrators must keep more than the operating system kernel up to date. Supporting packages that handle storage, networking, and cloud integrations also need regular maintenance.On October 28, 2026, AWS&hellip;<\/p>\n","protected":false},"author":41,"featured_media":18305,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_lmt_disableupdate":"","_lmt_disable":"","footnotes":""},"categories":[69,91],"tags":[],"class_list":["post-18304","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-aws","category-linux"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO Pro 5.0.3 - aioseo.com -->\n\t<meta name=\"description\" content=\"Learn how to fix CVE-2026-15957 on Amazon Linux 2. Check affected amazon-efs-utils versions, apply the AWS update, and validate EFS workloads.\" \/>\n\t<meta name=\"robots\" content=\"max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n\t<meta name=\"author\" content=\"Tanisha Mathew\"\/>\n\t<link rel=\"canonical\" href=\"https:\/\/www.supportpro.com\/blog\/amazon-linux-2-efs-utils-update-cve-2026-15957\/\" \/>\n\t\t<meta name=\"generator\" content=\"All in One SEO Pro (AIOSEO) 5.0.3\" \/>\n\t\t<meta property=\"og:locale\" content=\"en_US\" \/>\n\t\t<meta property=\"og:site_name\" content=\"Server Management Tips | SupportPRO Blog\" \/>\n\t\t<meta property=\"og:type\" content=\"article\" \/>\n\t\t<meta property=\"og:title\" content=\"Amazon Linux 2 EFS Update: Fix CVE-2026-15957\" \/>\n\t\t<meta property=\"og:description\" content=\"Learn how to fix CVE-2026-15957 on Amazon Linux 2. Check affected amazon-efs-utils versions, apply the AWS update, and validate EFS workloads.\" \/>\n\t\t<meta property=\"og:url\" content=\"https:\/\/www.supportpro.com\/blog\/amazon-linux-2-efs-utils-update-cve-2026-15957\/\" \/>\n\t\t<meta property=\"og:image\" content=\"https:\/\/www.supportpro.com\/blog\/wp-content\/uploads\/2026\/10\/Amazon-Linux-2-EFS-Utilities-Security-Update-What-Administrators-Should-Check.png\" \/>\n\t\t<meta property=\"og:image:secure_url\" content=\"https:\/\/www.supportpro.com\/blog\/wp-content\/uploads\/2026\/10\/Amazon-Linux-2-EFS-Utilities-Security-Update-What-Administrators-Should-Check.png\" \/>\n\t\t<meta property=\"og:image:width\" content=\"1366\" \/>\n\t\t<meta property=\"og:image:height\" content=\"768\" \/>\n\t\t<meta property=\"article:published_time\" content=\"2026-10-30T11:54:43+00:00\" \/>\n\t\t<meta property=\"article:modified_time\" content=\"2026-10-30T11:55:11+00:00\" \/>\n\t\t<meta name=\"twitter:card\" content=\"summary\" \/>\n\t\t<meta name=\"twitter:title\" content=\"Amazon Linux 2 EFS Update: Fix CVE-2026-15957\" \/>\n\t\t<meta name=\"twitter:description\" content=\"Learn how to fix CVE-2026-15957 on Amazon Linux 2. Check affected amazon-efs-utils versions, apply the AWS update, and validate EFS workloads.\" \/>\n\t\t<meta name=\"twitter:image\" content=\"https:\/\/www.supportpro.com\/blog\/wp-content\/uploads\/2026\/10\/Amazon-Linux-2-EFS-Utilities-Security-Update-What-Administrators-Should-Check.png\" \/>\n\t\t<script type=\"application\/ld+json\" class=\"aioseo-schema\">\n\t\t\t{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/amazon-linux-2-efs-utils-update-cve-2026-15957\\\/#article\",\"name\":\"Amazon Linux 2 EFS Update: Fix CVE-2026-15957\",\"headline\":\"CVE-2026-15957: Is Your Amazon Linux 2 Server Affected?\",\"author\":{\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/author\\\/tanisha-marmiasystems-com\\\/#author\"},\"publisher\":{\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/#organization\"},\"image\":{\"@type\":\"ImageObject\",\"url\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/wp-content\\\/uploads\\\/2026\\\/10\\\/Amazon-Linux-2-EFS-Utilities-Security-Update-What-Administrators-Should-Check.png\",\"width\":1366,\"height\":768,\"caption\":\"Amazon Linux 2 EFS Utilities Security Update: What Administrators Should Check Introduction Keeping Linux systems secure requires more than applying updates to the operating system kernel. Utilities that support storage, networking, and cloud service integrations also need regular security reviews. For administrators running Amazon Linux 2 workloads with Amazon Elastic File System (Amazon EFS), a newly published security advisory highlights the importance of checking these supporting packages. On October 28, 2026, Amazon Web Services (AWS) released security advisory ALAS2-2026-4044, addressing CVE-2026-15957 in the amazon-efs-utils package. AWS classifies the advisory as Important and identifies amazon-efs-utils-3.1.3-1.amzn2 as the corrected package. The underlying vulnerability involves uncontrolled recursion in Smithy-RS-generated deserialization functions, which can exhaust the stack and cause a process to abort. For Linux administrators, hosting providers, managed service providers (MSPs), and DevOps teams, the immediate priority is to identify affected hosts, apply the available security update, and confirm that EFS-dependent workloads continue to operate correctly. What Is the Amazon Linux 2 EFS Utilities Security Update? The amazon-efs-utils package provides utilities that help Linux instances connect to and use Amazon EFS. These utilities support EFS mount operations and related functionality used by applications that depend on shared file storage. AWS published ALAS2-2026-4044 to address a vulnerability affecting this package on Amazon Linux 2. The advisory identifies the following details: Security advisory: ALAS2-2026-4044 Release date: October 28, 2026 Affected package: amazon-efs-utils Vulnerability: CVE-2026-15957 AWS severity: Important Corrected package: amazon-efs-utils-3.1.3-1.amzn2 The corrected package is available for both x86_64 and ARM64 (aarch64) architectures. Administrators can review the official AWS Amazon Linux 2 security advisory for the complete package and remediation details. Understanding CVE-2026-15957 and Its Potential Impact CVE-2026-15957 concerns uncontrolled recursion in deserialization functions generated by the Smithy-RS code generation framework. Smithy-RS is used to generate Rust-based HTTP clients and servers, including components that support the AWS SDK for Rust. The affected deserialization functions handle JSON, CBOR, and XML data. When these functions process deeply nested data associated with a recursive model, uncontrolled recursion can consume excessive stack space. In a vulnerable, reachable component, an attacker may be able to trigger stack exhaustion and cause the affected process to abort. This is primarily a denial-of-service (DoS) risk, rather than a vulnerability that directly implies data theft or unauthorized modification. For infrastructure teams, the operational concern is that a process failure can interrupt a service that depends on the affected component. The actual impact depends on how the vulnerable functionality is exposed and used within the environment. The advisory identifies amazon-efs-utils as the affected Amazon Linux 2 package. However, administrators should not assume that every EFS mount is directly exploitable or that an existing mount will necessarily fail because of this vulnerability. Instead, they should prioritize the package update and verify the availability of applications and services that rely on EFS. Tenable also provides a Nessus plugin for ALAS2-2026-4044, which identifies systems running an affected package version. Its scanner classification differs from AWS's advisory severity, so teams should follow their organization's vulnerability assessment and prioritization procedures. How to Identify Affected Amazon Linux 2 Hosts The first step is to determine which instances have the affected package installed and whether they have received the corrected version. 1. Check the installed package version Connect to the Amazon Linux 2 instance and run: rpm -q amazon-efs-utils Review the output and compare the installed version with the corrected release, 3.1.3-1.amzn2. Versions earlier than the corrected release are identified as affected by the advisory. For environments with multiple instances, use configuration management, inventory tools, or vulnerability scanners to identify affected hosts across the fleet. 2. Review the advisory-specific update Check whether the security update is available through the configured package repositories: sudo yum updateinfo info ALAS2-2026-4044 Repository metadata and available update information can vary depending on the system's configuration. If the command does not return the expected information, review repository connectivity and metadata before concluding that the host is unaffected. 3. Prioritize EFS-dependent systems Pay particular attention to production servers that use EFS for shared application files, uploads, content directories, or other persistent data. Record the affected instances, their installed package versions, the applications using EFS, and the appropriate maintenance arrangements. This inventory helps teams coordinate remediation without overlooking workloads that are not frequently accessed or monitored. How to Apply the Security Update AWS provides two remediation options for Amazon Linux 2. To update only the EFS utilities package, run: sudo yum update amazon-efs-utils Alternatively, to apply the update associated with the specific security advisory, run: sudo yum update --advisory ALAS2-2026-4044 Choose the approach that fits your patch management policy. Updating the specific package may help limit the scope of a targeted maintenance operation, while advisory-based updates can be useful when tracking remediation against a particular security bulletin. Before making changes on production systems, review the package transaction and follow your organization's change management procedures. For managed hosting environments, consider staging the update on a representative instance before proceeding with a wider rollout. After installation, confirm the package version: rpm -q amazon-efs-utils Verify that the installed release matches the corrected package version or a later applicable fixed release. If the update fails, investigate repository availability, package dependencies, and any package management errors. Avoid assuming that an update was successful simply because the command was executed. What to Validate After Updating EFS Utilities Applying the patch is only part of the remediation process. Administrators should also verify that EFS-dependent applications continue to function as expected. Check EFS mount status. Review the mounted filesystems and confirm that the expected EFS mount points remain available: findmnt -t nfs4 Amazon EFS commonly uses NFSv4.1 for Linux mounts, so reviewing NFSv4 mount entries can help confirm that expected filesystems are present. Test application-level access. Verify that applications can read and write to their designated EFS directories using the appropriate service accounts and permissions. A successful mount alone does not guarantee that every application has the required access. Review system logs. Check relevant system and application logs for mount failures, permission errors, unexpected process exits, or other symptoms following the update. Monitor dependent workloads. For production systems, monitor application health, request failures, background jobs, and services that rely on shared EFS storage. Compare the results against the expected baseline and investigate any unexpected changes. Document remediation. Record the package version before and after the update, the affected hosts, the maintenance window, and the validation results. This information supports internal security reviews and compliance reporting. These checks help establish that the vulnerability has been addressed without introducing avoidable disruption to dependent services. Security Considerations for Amazon Linux 2 Environments Amazon Linux 2 is now an end-of-support (EOS) operating system, as identified in the AWS advisory. Organizations that continue to operate Amazon Linux 2 should therefore review both immediate security fixes and their longer-term operating system strategy. Applying available security updates remains important for systems that are still in use. However, individual package updates should not be treated as a substitute for evaluating the risks of continuing to run an EOS platform. Hosting providers and MSPs should maintain an accurate inventory of legacy instances, track applicable security advisories, and establish a migration plan for workloads that can move to a supported operating system. Migration planning should account for application compatibility, package availability, EFS integration, and operational dependencies. For DevOps teams, automated package inventory and vulnerability scanning can help identify outdated components before they become overlooked maintenance issues. A repeatable process for remediation and post-update validation also makes security response more consistent across environments. Conclusion The Amazon Linux 2 EFS utilities security update ALAS2-2026-4044 addresses CVE-2026-15957, a denial-of-service vulnerability involving uncontrolled deserialization recursion. AWS released the advisory on October 28, 2026, and identifies amazon-efs-utils-3.1.3-1.amzn2 as the corrected package. Administrators should check installed package versions, identify affected hosts, apply the appropriate update, and validate EFS mounts and dependent applications. Organizations running Amazon Linux 2 should also consider the operating system's end-of-support status when planning ongoing security maintenance. If your environment includes multiple Amazon Linux 2 instances, our team can assist with identifying affected hosts, coordinating the required updates, and validating EFS-dependent workloads to help minimize operational disruption.\"},\"datePublished\":\"2026-10-30T05:54:43-06:00\",\"dateModified\":\"2026-10-30T05:55:11-06:00\",\"inLanguage\":\"en-US\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/amazon-linux-2-efs-utils-update-cve-2026-15957\\\/#webpage\"},\"isPartOf\":{\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/amazon-linux-2-efs-utils-update-cve-2026-15957\\\/#webpage\"},\"articleSection\":\"AWS, Linux\"},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/amazon-linux-2-efs-utils-update-cve-2026-15957\\\/#breadcrumblist\",\"itemListElement\":[{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/#listItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/\",\"nextItem\":{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/category\\\/aws\\\/#listItem\",\"name\":\"AWS\"}},{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/category\\\/aws\\\/#listItem\",\"position\":2,\"name\":\"AWS\",\"item\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/category\\\/aws\\\/\",\"nextItem\":{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/amazon-linux-2-efs-utils-update-cve-2026-15957\\\/#listItem\",\"name\":\"CVE-2026-15957: Is Your Amazon Linux 2 Server Affected?\"},\"previousItem\":{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/#listItem\",\"name\":\"Home\"}},{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/amazon-linux-2-efs-utils-update-cve-2026-15957\\\/#listItem\",\"position\":3,\"name\":\"CVE-2026-15957: Is Your Amazon Linux 2 Server Affected?\",\"previousItem\":{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/category\\\/aws\\\/#listItem\",\"name\":\"AWS\"}}]},{\"@type\":\"Organization\",\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/#organization\",\"name\":\"SupportPRO\",\"description\":\"SupportPRO Blog\",\"url\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/\",\"telephone\":\"+18476076123\"},{\"@type\":\"Person\",\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/author\\\/tanisha-marmiasystems-com\\\/#author\",\"url\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/author\\\/tanisha-marmiasystems-com\\\/\",\"name\":\"Tanisha Mathew\",\"image\":{\"@type\":\"ImageObject\",\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/amazon-linux-2-efs-utils-update-cve-2026-15957\\\/#authorImage\",\"url\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/3a44dca8e0888dffd34573aa37d9bef5d6dfd090d786986af5e061eda54bec5f?s=96&d=mm&r=g\",\"width\":96,\"height\":96,\"caption\":\"Tanisha Mathew\"}},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/amazon-linux-2-efs-utils-update-cve-2026-15957\\\/#webpage\",\"url\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/amazon-linux-2-efs-utils-update-cve-2026-15957\\\/\",\"name\":\"Amazon Linux 2 EFS Update: Fix CVE-2026-15957\",\"description\":\"Learn how to fix CVE-2026-15957 on Amazon Linux 2. Check affected amazon-efs-utils versions, apply the AWS update, and validate EFS workloads.\",\"inLanguage\":\"en-US\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/#website\"},\"breadcrumb\":{\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/amazon-linux-2-efs-utils-update-cve-2026-15957\\\/#breadcrumblist\"},\"author\":{\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/author\\\/tanisha-marmiasystems-com\\\/#author\"},\"creator\":{\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/author\\\/tanisha-marmiasystems-com\\\/#author\"},\"image\":{\"@type\":\"ImageObject\",\"url\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/wp-content\\\/uploads\\\/2026\\\/10\\\/Amazon-Linux-2-EFS-Utilities-Security-Update-What-Administrators-Should-Check.png\",\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/amazon-linux-2-efs-utils-update-cve-2026-15957\\\/#mainImage\",\"width\":1366,\"height\":768,\"caption\":\"Amazon Linux 2 EFS Utilities Security Update: What Administrators Should Check Introduction Keeping Linux systems secure requires more than applying updates to the operating system kernel. Utilities that support storage, networking, and cloud service integrations also need regular security reviews. For administrators running Amazon Linux 2 workloads with Amazon Elastic File System (Amazon EFS), a newly published security advisory highlights the importance of checking these supporting packages. On October 28, 2026, Amazon Web Services (AWS) released security advisory ALAS2-2026-4044, addressing CVE-2026-15957 in the amazon-efs-utils package. AWS classifies the advisory as Important and identifies amazon-efs-utils-3.1.3-1.amzn2 as the corrected package. The underlying vulnerability involves uncontrolled recursion in Smithy-RS-generated deserialization functions, which can exhaust the stack and cause a process to abort. For Linux administrators, hosting providers, managed service providers (MSPs), and DevOps teams, the immediate priority is to identify affected hosts, apply the available security update, and confirm that EFS-dependent workloads continue to operate correctly. What Is the Amazon Linux 2 EFS Utilities Security Update? The amazon-efs-utils package provides utilities that help Linux instances connect to and use Amazon EFS. These utilities support EFS mount operations and related functionality used by applications that depend on shared file storage. AWS published ALAS2-2026-4044 to address a vulnerability affecting this package on Amazon Linux 2. The advisory identifies the following details: Security advisory: ALAS2-2026-4044 Release date: October 28, 2026 Affected package: amazon-efs-utils Vulnerability: CVE-2026-15957 AWS severity: Important Corrected package: amazon-efs-utils-3.1.3-1.amzn2 The corrected package is available for both x86_64 and ARM64 (aarch64) architectures. Administrators can review the official AWS Amazon Linux 2 security advisory for the complete package and remediation details. Understanding CVE-2026-15957 and Its Potential Impact CVE-2026-15957 concerns uncontrolled recursion in deserialization functions generated by the Smithy-RS code generation framework. Smithy-RS is used to generate Rust-based HTTP clients and servers, including components that support the AWS SDK for Rust. The affected deserialization functions handle JSON, CBOR, and XML data. When these functions process deeply nested data associated with a recursive model, uncontrolled recursion can consume excessive stack space. In a vulnerable, reachable component, an attacker may be able to trigger stack exhaustion and cause the affected process to abort. This is primarily a denial-of-service (DoS) risk, rather than a vulnerability that directly implies data theft or unauthorized modification. For infrastructure teams, the operational concern is that a process failure can interrupt a service that depends on the affected component. The actual impact depends on how the vulnerable functionality is exposed and used within the environment. The advisory identifies amazon-efs-utils as the affected Amazon Linux 2 package. However, administrators should not assume that every EFS mount is directly exploitable or that an existing mount will necessarily fail because of this vulnerability. Instead, they should prioritize the package update and verify the availability of applications and services that rely on EFS. Tenable also provides a Nessus plugin for ALAS2-2026-4044, which identifies systems running an affected package version. Its scanner classification differs from AWS's advisory severity, so teams should follow their organization's vulnerability assessment and prioritization procedures. How to Identify Affected Amazon Linux 2 Hosts The first step is to determine which instances have the affected package installed and whether they have received the corrected version. 1. Check the installed package version Connect to the Amazon Linux 2 instance and run: rpm -q amazon-efs-utils Review the output and compare the installed version with the corrected release, 3.1.3-1.amzn2. Versions earlier than the corrected release are identified as affected by the advisory. For environments with multiple instances, use configuration management, inventory tools, or vulnerability scanners to identify affected hosts across the fleet. 2. Review the advisory-specific update Check whether the security update is available through the configured package repositories: sudo yum updateinfo info ALAS2-2026-4044 Repository metadata and available update information can vary depending on the system's configuration. If the command does not return the expected information, review repository connectivity and metadata before concluding that the host is unaffected. 3. Prioritize EFS-dependent systems Pay particular attention to production servers that use EFS for shared application files, uploads, content directories, or other persistent data. Record the affected instances, their installed package versions, the applications using EFS, and the appropriate maintenance arrangements. This inventory helps teams coordinate remediation without overlooking workloads that are not frequently accessed or monitored. How to Apply the Security Update AWS provides two remediation options for Amazon Linux 2. To update only the EFS utilities package, run: sudo yum update amazon-efs-utils Alternatively, to apply the update associated with the specific security advisory, run: sudo yum update --advisory ALAS2-2026-4044 Choose the approach that fits your patch management policy. Updating the specific package may help limit the scope of a targeted maintenance operation, while advisory-based updates can be useful when tracking remediation against a particular security bulletin. Before making changes on production systems, review the package transaction and follow your organization's change management procedures. For managed hosting environments, consider staging the update on a representative instance before proceeding with a wider rollout. After installation, confirm the package version: rpm -q amazon-efs-utils Verify that the installed release matches the corrected package version or a later applicable fixed release. If the update fails, investigate repository availability, package dependencies, and any package management errors. Avoid assuming that an update was successful simply because the command was executed. What to Validate After Updating EFS Utilities Applying the patch is only part of the remediation process. Administrators should also verify that EFS-dependent applications continue to function as expected. Check EFS mount status. Review the mounted filesystems and confirm that the expected EFS mount points remain available: findmnt -t nfs4 Amazon EFS commonly uses NFSv4.1 for Linux mounts, so reviewing NFSv4 mount entries can help confirm that expected filesystems are present. Test application-level access. Verify that applications can read and write to their designated EFS directories using the appropriate service accounts and permissions. A successful mount alone does not guarantee that every application has the required access. Review system logs. Check relevant system and application logs for mount failures, permission errors, unexpected process exits, or other symptoms following the update. Monitor dependent workloads. For production systems, monitor application health, request failures, background jobs, and services that rely on shared EFS storage. Compare the results against the expected baseline and investigate any unexpected changes. Document remediation. Record the package version before and after the update, the affected hosts, the maintenance window, and the validation results. This information supports internal security reviews and compliance reporting. These checks help establish that the vulnerability has been addressed without introducing avoidable disruption to dependent services. Security Considerations for Amazon Linux 2 Environments Amazon Linux 2 is now an end-of-support (EOS) operating system, as identified in the AWS advisory. Organizations that continue to operate Amazon Linux 2 should therefore review both immediate security fixes and their longer-term operating system strategy. Applying available security updates remains important for systems that are still in use. However, individual package updates should not be treated as a substitute for evaluating the risks of continuing to run an EOS platform. Hosting providers and MSPs should maintain an accurate inventory of legacy instances, track applicable security advisories, and establish a migration plan for workloads that can move to a supported operating system. Migration planning should account for application compatibility, package availability, EFS integration, and operational dependencies. For DevOps teams, automated package inventory and vulnerability scanning can help identify outdated components before they become overlooked maintenance issues. A repeatable process for remediation and post-update validation also makes security response more consistent across environments. Conclusion The Amazon Linux 2 EFS utilities security update ALAS2-2026-4044 addresses CVE-2026-15957, a denial-of-service vulnerability involving uncontrolled deserialization recursion. AWS released the advisory on October 28, 2026, and identifies amazon-efs-utils-3.1.3-1.amzn2 as the corrected package. Administrators should check installed package versions, identify affected hosts, apply the appropriate update, and validate EFS mounts and dependent applications. Organizations running Amazon Linux 2 should also consider the operating system's end-of-support status when planning ongoing security maintenance. If your environment includes multiple Amazon Linux 2 instances, our team can assist with identifying affected hosts, coordinating the required updates, and validating EFS-dependent workloads to help minimize operational disruption.\"},\"primaryImageOfPage\":{\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/amazon-linux-2-efs-utils-update-cve-2026-15957\\\/#mainImage\"},\"datePublished\":\"2026-10-30T05:54:43-06:00\",\"dateModified\":\"2026-10-30T05:55:11-06:00\"},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/#website\",\"url\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/\",\"name\":\"Server Management Tips\",\"description\":\"SupportPRO Blog\",\"inLanguage\":\"en-US\",\"publisher\":{\"@id\":\"https:\\\/\\\/www.supportpro.com\\\/blog\\\/#organization\"}}]}\n\t\t<\/script>\n\t\t<!-- All in One SEO Pro -->\r\n\t\t<title>Amazon Linux 2 EFS Update: Fix CVE-2026-15957<\/title>\n\n","aioseo_head_json":{"title":"Amazon Linux 2 EFS Update: Fix CVE-2026-15957","description":"Learn how to fix CVE-2026-15957 on Amazon Linux 2. Check affected amazon-efs-utils versions, apply the AWS update, and validate EFS workloads.","canonical_url":"https:\/\/www.supportpro.com\/blog\/amazon-linux-2-efs-utils-update-cve-2026-15957\/","robots":"max-snippet:-1, max-image-preview:large, max-video-preview:-1","keywords":"","webmasterTools":{"miscellaneous":""},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/www.supportpro.com\/blog\/amazon-linux-2-efs-utils-update-cve-2026-15957\/#article","name":"Amazon Linux 2 EFS Update: Fix CVE-2026-15957","headline":"CVE-2026-15957: Is Your Amazon Linux 2 Server Affected?","author":{"@id":"https:\/\/www.supportpro.com\/blog\/author\/tanisha-marmiasystems-com\/#author"},"publisher":{"@id":"https:\/\/www.supportpro.com\/blog\/#organization"},"image":{"@type":"ImageObject","url":"https:\/\/www.supportpro.com\/blog\/wp-content\/uploads\/2026\/10\/Amazon-Linux-2-EFS-Utilities-Security-Update-What-Administrators-Should-Check.png","width":1366,"height":768,"caption":"Amazon Linux 2 EFS Utilities Security Update: What Administrators Should Check Introduction Keeping Linux systems secure requires more than applying updates to the operating system kernel. Utilities that support storage, networking, and cloud service integrations also need regular security reviews. For administrators running Amazon Linux 2 workloads with Amazon Elastic File System (Amazon EFS), a newly published security advisory highlights the importance of checking these supporting packages. On October 28, 2026, Amazon Web Services (AWS) released security advisory ALAS2-2026-4044, addressing CVE-2026-15957 in the amazon-efs-utils package. AWS classifies the advisory as Important and identifies amazon-efs-utils-3.1.3-1.amzn2 as the corrected package. The underlying vulnerability involves uncontrolled recursion in Smithy-RS-generated deserialization functions, which can exhaust the stack and cause a process to abort. For Linux administrators, hosting providers, managed service providers (MSPs), and DevOps teams, the immediate priority is to identify affected hosts, apply the available security update, and confirm that EFS-dependent workloads continue to operate correctly. What Is the Amazon Linux 2 EFS Utilities Security Update? The amazon-efs-utils package provides utilities that help Linux instances connect to and use Amazon EFS. These utilities support EFS mount operations and related functionality used by applications that depend on shared file storage. AWS published ALAS2-2026-4044 to address a vulnerability affecting this package on Amazon Linux 2. The advisory identifies the following details: Security advisory: ALAS2-2026-4044 Release date: October 28, 2026 Affected package: amazon-efs-utils Vulnerability: CVE-2026-15957 AWS severity: Important Corrected package: amazon-efs-utils-3.1.3-1.amzn2 The corrected package is available for both x86_64 and ARM64 (aarch64) architectures. Administrators can review the official AWS Amazon Linux 2 security advisory for the complete package and remediation details. Understanding CVE-2026-15957 and Its Potential Impact CVE-2026-15957 concerns uncontrolled recursion in deserialization functions generated by the Smithy-RS code generation framework. Smithy-RS is used to generate Rust-based HTTP clients and servers, including components that support the AWS SDK for Rust. The affected deserialization functions handle JSON, CBOR, and XML data. When these functions process deeply nested data associated with a recursive model, uncontrolled recursion can consume excessive stack space. In a vulnerable, reachable component, an attacker may be able to trigger stack exhaustion and cause the affected process to abort. This is primarily a denial-of-service (DoS) risk, rather than a vulnerability that directly implies data theft or unauthorized modification. For infrastructure teams, the operational concern is that a process failure can interrupt a service that depends on the affected component. The actual impact depends on how the vulnerable functionality is exposed and used within the environment. The advisory identifies amazon-efs-utils as the affected Amazon Linux 2 package. However, administrators should not assume that every EFS mount is directly exploitable or that an existing mount will necessarily fail because of this vulnerability. Instead, they should prioritize the package update and verify the availability of applications and services that rely on EFS. Tenable also provides a Nessus plugin for ALAS2-2026-4044, which identifies systems running an affected package version. Its scanner classification differs from AWS's advisory severity, so teams should follow their organization's vulnerability assessment and prioritization procedures. How to Identify Affected Amazon Linux 2 Hosts The first step is to determine which instances have the affected package installed and whether they have received the corrected version. 1. Check the installed package version Connect to the Amazon Linux 2 instance and run: rpm -q amazon-efs-utils Review the output and compare the installed version with the corrected release, 3.1.3-1.amzn2. Versions earlier than the corrected release are identified as affected by the advisory. For environments with multiple instances, use configuration management, inventory tools, or vulnerability scanners to identify affected hosts across the fleet. 2. Review the advisory-specific update Check whether the security update is available through the configured package repositories: sudo yum updateinfo info ALAS2-2026-4044 Repository metadata and available update information can vary depending on the system's configuration. If the command does not return the expected information, review repository connectivity and metadata before concluding that the host is unaffected. 3. Prioritize EFS-dependent systems Pay particular attention to production servers that use EFS for shared application files, uploads, content directories, or other persistent data. Record the affected instances, their installed package versions, the applications using EFS, and the appropriate maintenance arrangements. This inventory helps teams coordinate remediation without overlooking workloads that are not frequently accessed or monitored. How to Apply the Security Update AWS provides two remediation options for Amazon Linux 2. To update only the EFS utilities package, run: sudo yum update amazon-efs-utils Alternatively, to apply the update associated with the specific security advisory, run: sudo yum update --advisory ALAS2-2026-4044 Choose the approach that fits your patch management policy. Updating the specific package may help limit the scope of a targeted maintenance operation, while advisory-based updates can be useful when tracking remediation against a particular security bulletin. Before making changes on production systems, review the package transaction and follow your organization's change management procedures. For managed hosting environments, consider staging the update on a representative instance before proceeding with a wider rollout. After installation, confirm the package version: rpm -q amazon-efs-utils Verify that the installed release matches the corrected package version or a later applicable fixed release. If the update fails, investigate repository availability, package dependencies, and any package management errors. Avoid assuming that an update was successful simply because the command was executed. What to Validate After Updating EFS Utilities Applying the patch is only part of the remediation process. Administrators should also verify that EFS-dependent applications continue to function as expected. Check EFS mount status. Review the mounted filesystems and confirm that the expected EFS mount points remain available: findmnt -t nfs4 Amazon EFS commonly uses NFSv4.1 for Linux mounts, so reviewing NFSv4 mount entries can help confirm that expected filesystems are present. Test application-level access. Verify that applications can read and write to their designated EFS directories using the appropriate service accounts and permissions. A successful mount alone does not guarantee that every application has the required access. Review system logs. Check relevant system and application logs for mount failures, permission errors, unexpected process exits, or other symptoms following the update. Monitor dependent workloads. For production systems, monitor application health, request failures, background jobs, and services that rely on shared EFS storage. Compare the results against the expected baseline and investigate any unexpected changes. Document remediation. Record the package version before and after the update, the affected hosts, the maintenance window, and the validation results. This information supports internal security reviews and compliance reporting. These checks help establish that the vulnerability has been addressed without introducing avoidable disruption to dependent services. Security Considerations for Amazon Linux 2 Environments Amazon Linux 2 is now an end-of-support (EOS) operating system, as identified in the AWS advisory. Organizations that continue to operate Amazon Linux 2 should therefore review both immediate security fixes and their longer-term operating system strategy. Applying available security updates remains important for systems that are still in use. However, individual package updates should not be treated as a substitute for evaluating the risks of continuing to run an EOS platform. Hosting providers and MSPs should maintain an accurate inventory of legacy instances, track applicable security advisories, and establish a migration plan for workloads that can move to a supported operating system. Migration planning should account for application compatibility, package availability, EFS integration, and operational dependencies. For DevOps teams, automated package inventory and vulnerability scanning can help identify outdated components before they become overlooked maintenance issues. A repeatable process for remediation and post-update validation also makes security response more consistent across environments. Conclusion The Amazon Linux 2 EFS utilities security update ALAS2-2026-4044 addresses CVE-2026-15957, a denial-of-service vulnerability involving uncontrolled deserialization recursion. AWS released the advisory on October 28, 2026, and identifies amazon-efs-utils-3.1.3-1.amzn2 as the corrected package. Administrators should check installed package versions, identify affected hosts, apply the appropriate update, and validate EFS mounts and dependent applications. Organizations running Amazon Linux 2 should also consider the operating system's end-of-support status when planning ongoing security maintenance. If your environment includes multiple Amazon Linux 2 instances, our team can assist with identifying affected hosts, coordinating the required updates, and validating EFS-dependent workloads to help minimize operational disruption."},"datePublished":"2026-10-30T05:54:43-06:00","dateModified":"2026-10-30T05:55:11-06:00","inLanguage":"en-US","mainEntityOfPage":{"@id":"https:\/\/www.supportpro.com\/blog\/amazon-linux-2-efs-utils-update-cve-2026-15957\/#webpage"},"isPartOf":{"@id":"https:\/\/www.supportpro.com\/blog\/amazon-linux-2-efs-utils-update-cve-2026-15957\/#webpage"},"articleSection":"AWS, Linux"},{"@type":"BreadcrumbList","@id":"https:\/\/www.supportpro.com\/blog\/amazon-linux-2-efs-utils-update-cve-2026-15957\/#breadcrumblist","itemListElement":[{"@type":"ListItem","@id":"https:\/\/www.supportpro.com\/blog\/#listItem","position":1,"name":"Home","item":"https:\/\/www.supportpro.com\/blog\/","nextItem":{"@type":"ListItem","@id":"https:\/\/www.supportpro.com\/blog\/category\/aws\/#listItem","name":"AWS"}},{"@type":"ListItem","@id":"https:\/\/www.supportpro.com\/blog\/category\/aws\/#listItem","position":2,"name":"AWS","item":"https:\/\/www.supportpro.com\/blog\/category\/aws\/","nextItem":{"@type":"ListItem","@id":"https:\/\/www.supportpro.com\/blog\/amazon-linux-2-efs-utils-update-cve-2026-15957\/#listItem","name":"CVE-2026-15957: Is Your Amazon Linux 2 Server Affected?"},"previousItem":{"@type":"ListItem","@id":"https:\/\/www.supportpro.com\/blog\/#listItem","name":"Home"}},{"@type":"ListItem","@id":"https:\/\/www.supportpro.com\/blog\/amazon-linux-2-efs-utils-update-cve-2026-15957\/#listItem","position":3,"name":"CVE-2026-15957: Is Your Amazon Linux 2 Server Affected?","previousItem":{"@type":"ListItem","@id":"https:\/\/www.supportpro.com\/blog\/category\/aws\/#listItem","name":"AWS"}}]},{"@type":"Organization","@id":"https:\/\/www.supportpro.com\/blog\/#organization","name":"SupportPRO","description":"SupportPRO Blog","url":"https:\/\/www.supportpro.com\/blog\/","telephone":"+18476076123"},{"@type":"Person","@id":"https:\/\/www.supportpro.com\/blog\/author\/tanisha-marmiasystems-com\/#author","url":"https:\/\/www.supportpro.com\/blog\/author\/tanisha-marmiasystems-com\/","name":"Tanisha Mathew","image":{"@type":"ImageObject","@id":"https:\/\/www.supportpro.com\/blog\/amazon-linux-2-efs-utils-update-cve-2026-15957\/#authorImage","url":"https:\/\/secure.gravatar.com\/avatar\/3a44dca8e0888dffd34573aa37d9bef5d6dfd090d786986af5e061eda54bec5f?s=96&d=mm&r=g","width":96,"height":96,"caption":"Tanisha Mathew"}},{"@type":"WebPage","@id":"https:\/\/www.supportpro.com\/blog\/amazon-linux-2-efs-utils-update-cve-2026-15957\/#webpage","url":"https:\/\/www.supportpro.com\/blog\/amazon-linux-2-efs-utils-update-cve-2026-15957\/","name":"Amazon Linux 2 EFS Update: Fix CVE-2026-15957","description":"Learn how to fix CVE-2026-15957 on Amazon Linux 2. Check affected amazon-efs-utils versions, apply the AWS update, and validate EFS workloads.","inLanguage":"en-US","isPartOf":{"@id":"https:\/\/www.supportpro.com\/blog\/#website"},"breadcrumb":{"@id":"https:\/\/www.supportpro.com\/blog\/amazon-linux-2-efs-utils-update-cve-2026-15957\/#breadcrumblist"},"author":{"@id":"https:\/\/www.supportpro.com\/blog\/author\/tanisha-marmiasystems-com\/#author"},"creator":{"@id":"https:\/\/www.supportpro.com\/blog\/author\/tanisha-marmiasystems-com\/#author"},"image":{"@type":"ImageObject","url":"https:\/\/www.supportpro.com\/blog\/wp-content\/uploads\/2026\/10\/Amazon-Linux-2-EFS-Utilities-Security-Update-What-Administrators-Should-Check.png","@id":"https:\/\/www.supportpro.com\/blog\/amazon-linux-2-efs-utils-update-cve-2026-15957\/#mainImage","width":1366,"height":768,"caption":"Amazon Linux 2 EFS Utilities Security Update: What Administrators Should Check Introduction Keeping Linux systems secure requires more than applying updates to the operating system kernel. Utilities that support storage, networking, and cloud service integrations also need regular security reviews. For administrators running Amazon Linux 2 workloads with Amazon Elastic File System (Amazon EFS), a newly published security advisory highlights the importance of checking these supporting packages. On October 28, 2026, Amazon Web Services (AWS) released security advisory ALAS2-2026-4044, addressing CVE-2026-15957 in the amazon-efs-utils package. AWS classifies the advisory as Important and identifies amazon-efs-utils-3.1.3-1.amzn2 as the corrected package. The underlying vulnerability involves uncontrolled recursion in Smithy-RS-generated deserialization functions, which can exhaust the stack and cause a process to abort. For Linux administrators, hosting providers, managed service providers (MSPs), and DevOps teams, the immediate priority is to identify affected hosts, apply the available security update, and confirm that EFS-dependent workloads continue to operate correctly. What Is the Amazon Linux 2 EFS Utilities Security Update? The amazon-efs-utils package provides utilities that help Linux instances connect to and use Amazon EFS. These utilities support EFS mount operations and related functionality used by applications that depend on shared file storage. AWS published ALAS2-2026-4044 to address a vulnerability affecting this package on Amazon Linux 2. The advisory identifies the following details: Security advisory: ALAS2-2026-4044 Release date: October 28, 2026 Affected package: amazon-efs-utils Vulnerability: CVE-2026-15957 AWS severity: Important Corrected package: amazon-efs-utils-3.1.3-1.amzn2 The corrected package is available for both x86_64 and ARM64 (aarch64) architectures. Administrators can review the official AWS Amazon Linux 2 security advisory for the complete package and remediation details. Understanding CVE-2026-15957 and Its Potential Impact CVE-2026-15957 concerns uncontrolled recursion in deserialization functions generated by the Smithy-RS code generation framework. Smithy-RS is used to generate Rust-based HTTP clients and servers, including components that support the AWS SDK for Rust. The affected deserialization functions handle JSON, CBOR, and XML data. When these functions process deeply nested data associated with a recursive model, uncontrolled recursion can consume excessive stack space. In a vulnerable, reachable component, an attacker may be able to trigger stack exhaustion and cause the affected process to abort. This is primarily a denial-of-service (DoS) risk, rather than a vulnerability that directly implies data theft or unauthorized modification. For infrastructure teams, the operational concern is that a process failure can interrupt a service that depends on the affected component. The actual impact depends on how the vulnerable functionality is exposed and used within the environment. The advisory identifies amazon-efs-utils as the affected Amazon Linux 2 package. However, administrators should not assume that every EFS mount is directly exploitable or that an existing mount will necessarily fail because of this vulnerability. Instead, they should prioritize the package update and verify the availability of applications and services that rely on EFS. Tenable also provides a Nessus plugin for ALAS2-2026-4044, which identifies systems running an affected package version. Its scanner classification differs from AWS's advisory severity, so teams should follow their organization's vulnerability assessment and prioritization procedures. How to Identify Affected Amazon Linux 2 Hosts The first step is to determine which instances have the affected package installed and whether they have received the corrected version. 1. Check the installed package version Connect to the Amazon Linux 2 instance and run: rpm -q amazon-efs-utils Review the output and compare the installed version with the corrected release, 3.1.3-1.amzn2. Versions earlier than the corrected release are identified as affected by the advisory. For environments with multiple instances, use configuration management, inventory tools, or vulnerability scanners to identify affected hosts across the fleet. 2. Review the advisory-specific update Check whether the security update is available through the configured package repositories: sudo yum updateinfo info ALAS2-2026-4044 Repository metadata and available update information can vary depending on the system's configuration. If the command does not return the expected information, review repository connectivity and metadata before concluding that the host is unaffected. 3. Prioritize EFS-dependent systems Pay particular attention to production servers that use EFS for shared application files, uploads, content directories, or other persistent data. Record the affected instances, their installed package versions, the applications using EFS, and the appropriate maintenance arrangements. This inventory helps teams coordinate remediation without overlooking workloads that are not frequently accessed or monitored. How to Apply the Security Update AWS provides two remediation options for Amazon Linux 2. To update only the EFS utilities package, run: sudo yum update amazon-efs-utils Alternatively, to apply the update associated with the specific security advisory, run: sudo yum update --advisory ALAS2-2026-4044 Choose the approach that fits your patch management policy. Updating the specific package may help limit the scope of a targeted maintenance operation, while advisory-based updates can be useful when tracking remediation against a particular security bulletin. Before making changes on production systems, review the package transaction and follow your organization's change management procedures. For managed hosting environments, consider staging the update on a representative instance before proceeding with a wider rollout. After installation, confirm the package version: rpm -q amazon-efs-utils Verify that the installed release matches the corrected package version or a later applicable fixed release. If the update fails, investigate repository availability, package dependencies, and any package management errors. Avoid assuming that an update was successful simply because the command was executed. What to Validate After Updating EFS Utilities Applying the patch is only part of the remediation process. Administrators should also verify that EFS-dependent applications continue to function as expected. Check EFS mount status. Review the mounted filesystems and confirm that the expected EFS mount points remain available: findmnt -t nfs4 Amazon EFS commonly uses NFSv4.1 for Linux mounts, so reviewing NFSv4 mount entries can help confirm that expected filesystems are present. Test application-level access. Verify that applications can read and write to their designated EFS directories using the appropriate service accounts and permissions. A successful mount alone does not guarantee that every application has the required access. Review system logs. Check relevant system and application logs for mount failures, permission errors, unexpected process exits, or other symptoms following the update. Monitor dependent workloads. For production systems, monitor application health, request failures, background jobs, and services that rely on shared EFS storage. Compare the results against the expected baseline and investigate any unexpected changes. Document remediation. Record the package version before and after the update, the affected hosts, the maintenance window, and the validation results. This information supports internal security reviews and compliance reporting. These checks help establish that the vulnerability has been addressed without introducing avoidable disruption to dependent services. Security Considerations for Amazon Linux 2 Environments Amazon Linux 2 is now an end-of-support (EOS) operating system, as identified in the AWS advisory. Organizations that continue to operate Amazon Linux 2 should therefore review both immediate security fixes and their longer-term operating system strategy. Applying available security updates remains important for systems that are still in use. However, individual package updates should not be treated as a substitute for evaluating the risks of continuing to run an EOS platform. Hosting providers and MSPs should maintain an accurate inventory of legacy instances, track applicable security advisories, and establish a migration plan for workloads that can move to a supported operating system. Migration planning should account for application compatibility, package availability, EFS integration, and operational dependencies. For DevOps teams, automated package inventory and vulnerability scanning can help identify outdated components before they become overlooked maintenance issues. A repeatable process for remediation and post-update validation also makes security response more consistent across environments. Conclusion The Amazon Linux 2 EFS utilities security update ALAS2-2026-4044 addresses CVE-2026-15957, a denial-of-service vulnerability involving uncontrolled deserialization recursion. AWS released the advisory on October 28, 2026, and identifies amazon-efs-utils-3.1.3-1.amzn2 as the corrected package. Administrators should check installed package versions, identify affected hosts, apply the appropriate update, and validate EFS mounts and dependent applications. Organizations running Amazon Linux 2 should also consider the operating system's end-of-support status when planning ongoing security maintenance. If your environment includes multiple Amazon Linux 2 instances, our team can assist with identifying affected hosts, coordinating the required updates, and validating EFS-dependent workloads to help minimize operational disruption."},"primaryImageOfPage":{"@id":"https:\/\/www.supportpro.com\/blog\/amazon-linux-2-efs-utils-update-cve-2026-15957\/#mainImage"},"datePublished":"2026-10-30T05:54:43-06:00","dateModified":"2026-10-30T05:55:11-06:00"},{"@type":"WebSite","@id":"https:\/\/www.supportpro.com\/blog\/#website","url":"https:\/\/www.supportpro.com\/blog\/","name":"Server Management Tips","description":"SupportPRO Blog","inLanguage":"en-US","publisher":{"@id":"https:\/\/www.supportpro.com\/blog\/#organization"}}]},"og:locale":"en_US","og:site_name":"Server Management Tips | SupportPRO Blog","og:type":"article","og:title":"Amazon Linux 2 EFS Update: Fix CVE-2026-15957","og:description":"Learn how to fix CVE-2026-15957 on Amazon Linux 2. Check affected amazon-efs-utils versions, apply the AWS update, and validate EFS workloads.","og:url":"https:\/\/www.supportpro.com\/blog\/amazon-linux-2-efs-utils-update-cve-2026-15957\/","og:image":"https:\/\/www.supportpro.com\/blog\/wp-content\/uploads\/2026\/10\/Amazon-Linux-2-EFS-Utilities-Security-Update-What-Administrators-Should-Check.png","og:image:secure_url":"https:\/\/www.supportpro.com\/blog\/wp-content\/uploads\/2026\/10\/Amazon-Linux-2-EFS-Utilities-Security-Update-What-Administrators-Should-Check.png","og:image:width":1366,"og:image:height":768,"article:published_time":"2026-10-30T11:54:43+00:00","article:modified_time":"2026-10-30T11:55:11+00:00","twitter:card":"summary","twitter:title":"Amazon Linux 2 EFS Update: Fix CVE-2026-15957","twitter:description":"Learn how to fix CVE-2026-15957 on Amazon Linux 2. Check affected amazon-efs-utils versions, apply the AWS update, and validate EFS workloads.","twitter:image":"https:\/\/www.supportpro.com\/blog\/wp-content\/uploads\/2026\/10\/Amazon-Linux-2-EFS-Utilities-Security-Update-What-Administrators-Should-Check.png"},"aioseo_meta_data":{"post_id":"18304","title":"Amazon Linux 2 EFS Update: Fix CVE-2026-15957","description":"Learn how to fix CVE-2026-15957 on Amazon Linux 2. Check affected amazon-efs-utils versions, apply the AWS update, and validate EFS workloads.","keywords":null,"keyphrases":{"focus":{"keyphrase":"Amazon Linux 2 EFS","score":0,"analysis":[]},"additional":[{"keyphrase":"Amazon Linux 2 security update","score":0},{"keyphrase":"CVE-2026-15957","score":0},{"keyphrase":"amazon-efs-utils vulnerability","score":0},{"keyphrase":"Amazon EFS security update","score":0},{"keyphrase":"ALAS2-2026-404","score":0}]},"primary_term":null,"canonical_url":null,"og_title":null,"og_description":null,"og_object_type":"default","og_image_type":"default","og_image_url":null,"og_image_width":null,"og_image_height":null,"og_image_custom_url":null,"og_image_custom_fields":null,"og_video":"","og_custom_url":null,"og_article_section":null,"og_article_tags":null,"twitter_use_og":false,"twitter_card":"default","twitter_image_type":"default","twitter_image_url":null,"twitter_image_custom_url":null,"twitter_image_custom_fields":null,"twitter_title":null,"twitter_description":null,"schema":{"blockGraphs":[],"customGraphs":[],"default":{"data":{"Article":[],"Course":[],"Dataset":[],"FAQPage":[],"Movie":[],"Person":[],"Product":[],"ProductReview":[],"Car":[],"Recipe":[],"Service":[],"SoftwareApplication":[],"WebPage":[]},"graphName":"Article","isEnabled":true},"graphs":[]},"schema_type":"default","schema_type_options":null,"pillar_content":false,"robots_default":true,"robots_noindex":false,"robots_noarchive":false,"robots_nosnippet":false,"robots_nofollow":false,"robots_noimageindex":false,"robots_noodp":false,"robots_notranslate":false,"robots_max_snippet":"-1","robots_max_videopreview":"-1","robots_max_imagepreview":"large","priority":null,"frequency":"default","local_seo":null,"seo_analyzer_scan_date":"2026-10-30 11:56:06","breadcrumb_settings":null,"limit_modified_date":false,"open_ai":null,"ai":{"faqs":[],"keyPoints":[],"schemas":[],"titles":[],"descriptions":[],"socialPosts":{"email":{"subject":"","preview":"","content":""},"linkedin":[],"twitter":[],"facebook":[],"instagram":[]}},"created":"2026-10-30 09:50:09","updated":"2026-10-30 11:56:06","focus_keyword":"Amazon Linux 2 EFS","additional_keywords":[{"word":"Amazon Linux 2 security update","score":63,"items":{"introductionKeyword":{"score":3},"keyphraseLength":{"score":6},"keyphraseDensity":{"score":4},"functionWordsInKeyphrase":{"score":9},"textCompetingLinks":{"score":9},"imageKeyphrase":{"score":3}}},{"word":"CVE-2026-15957","score":89,"items":{"introductionKeyword":{"score":9},"keyphraseLength":{"score":9},"keyphraseDensity":{"score":9},"functionWordsInKeyphrase":{"score":9},"textCompetingLinks":{"score":9},"imageKeyphrase":{"score":3}}},{"word":"amazon-efs-utils vulnerability","score":69,"items":{"introductionKeyword":{"score":3},"keyphraseLength":{"score":9},"keyphraseDensity":{"score":4},"functionWordsInKeyphrase":{"score":9},"textCompetingLinks":{"score":9},"imageKeyphrase":{"score":3}}},{"word":"Amazon EFS security update","score":69,"items":{"introductionKeyword":{"score":3},"keyphraseLength":{"score":9},"keyphraseDensity":{"score":4},"functionWordsInKeyphrase":{"score":9},"textCompetingLinks":{"score":9},"imageKeyphrase":{"score":3}}},{"word":"ALAS2-2026-404","score":69,"items":{"introductionKeyword":{"score":3},"keyphraseLength":{"score":9},"keyphraseDensity":{"score":4},"functionWordsInKeyphrase":{"score":9},"textCompetingLinks":{"score":9},"imageKeyphrase":{"score":3}}}],"truseo_locale":null},"aioseo_breadcrumb":"<div class=\"aioseo-breadcrumbs\"><span class=\"aioseo-breadcrumb\">\n\t<a href=\"https:\/\/www.supportpro.com\/blog\/\" title=\"Home\">Home<\/a>\n<\/span><span class=\"aioseo-breadcrumb-separator\">\u00bb<\/span><span class=\"aioseo-breadcrumb\">\n\t<a href=\"https:\/\/www.supportpro.com\/blog\/category\/aws\/\" title=\"AWS\">AWS<\/a>\n<\/span><span class=\"aioseo-breadcrumb-separator\">\u00bb<\/span><span class=\"aioseo-breadcrumb\">\n\tCVE-2026-15957: Is Your Amazon Linux 2 Server Affected?\n<\/span><\/div>","aioseo_breadcrumb_json":[{"label":"Home","link":"https:\/\/www.supportpro.com\/blog\/"},{"label":"AWS","link":"https:\/\/www.supportpro.com\/blog\/category\/aws\/"},{"label":"CVE-2026-15957: Is Your Amazon Linux 2 Server Affected?","link":"https:\/\/www.supportpro.com\/blog\/amazon-linux-2-efs-utils-update-cve-2026-15957\/"}],"_links":{"self":[{"href":"https:\/\/www.supportpro.com\/blog\/wp-json\/wp\/v2\/posts\/18304","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.supportpro.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.supportpro.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.supportpro.com\/blog\/wp-json\/wp\/v2\/users\/41"}],"replies":[{"embeddable":true,"href":"https:\/\/www.supportpro.com\/blog\/wp-json\/wp\/v2\/comments?post=18304"}],"version-history":[{"count":1,"href":"https:\/\/www.supportpro.com\/blog\/wp-json\/wp\/v2\/posts\/18304\/revisions"}],"predecessor-version":[{"id":18306,"href":"https:\/\/www.supportpro.com\/blog\/wp-json\/wp\/v2\/posts\/18304\/revisions\/18306"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.supportpro.com\/blog\/wp-json\/wp\/v2\/media\/18305"}],"wp:attachment":[{"href":"https:\/\/www.supportpro.com\/blog\/wp-json\/wp\/v2\/media?parent=18304"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.supportpro.com\/blog\/wp-json\/wp\/v2\/categories?post=18304"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.supportpro.com\/blog\/wp-json\/wp\/v2\/tags?post=18304"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}