Red Hat Product Errata RHSA-2026:26491 - Security Advisory Issued: 2026-06-17 Updated: 2026-06-17 RHSA-2026:26491 - Security Advisory Overview Updated Packages Synopsis Important: firefox security update Type/Severity Security Advisory: Important Red Hat Lightspeed patch analysis Identify and remediate systems affected by this advisory. View affected systems Topic An update for firefox is now available for Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section. Description Mozilla Firefox is an open-source web browser, designed for standards compliance, performance, and portability. Security Fix(es): firefox: Incorrect boundary conditions in the JavaScript Engine: JIT component (CVE-2026-8388) firefox: Other issue in the JavaScript Engine component (CVE-2026-8391) firefox: Sandbox escape in the Profile Backup component (CVE-2026-8401) firefox: Integer overflow in the Networking: JAR component (CVE-2026-8956) firefox: Memory safety bugs fixed in Firefox ESR 115.36, Firefox ESR 140.11 and Firefox 151 (CVE-2026-8975) firefox: Privilege escalation in the DOM: Workers component (CVE-2026-8955) firefox: Denial-of-service due to invalid pointer in the Audio/Video: Web Codecs component (CVE-2026-8968) firefox: Incorrect boundary conditions, integer overflow in the Audio/Video component (CVE-2026-8954) firefox: Information disclosure, sandbox escape in the Security: Process Sandboxing component (CVE-2026-8958) firefox: Incorrect boundary conditions in the Audio/Video: Web Codecs component (CVE-2026-8946) firefox: Privilege escalation in the Security component (CVE-2026-8970) firefox: Same-origin policy bypass in the Networking: HTTP component (CVE-2026-8950) firefox: Memory safety bugs fixed in Firefox ESR 140.11 and Firefox 151 (CVE-2026-8974) firefox: Sandbox escape due to use-after-free in the Disability Access APIs component (CVE-2026-8953) firefox: Spoofing issue in the Form Autofill component (CVE-2026-8961) firefox: Use-after-free in the DOM: Bindings (WebIDL) component (CVE-2026-8947) firefox: Mitigation bypass in the DOM: Security component (CVE-2026-8962) firefox: Privilege escalation in the Enterprise Policies component (CVE-2026-8957) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section. Solution For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 Affected Products Red Hat Enterprise Linux Server - AUS 9.2 x86_64 Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 9.2 ppc64le Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 9.2 x86_64 Red Hat Enterprise Linux for ARM 64 - 4 years of updates 9.2 aarch64 Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 9.2 s390x Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 9.2 x86_64 Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle 9.2 aarch64 Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle 9.2 ppc64le Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle 9.2 s390x Fixes BZ - 2476469 - CVE-2026-8388 firefox: thunderbird: Incorrect boundary conditions in the JavaScript Engine: JIT component BZ - 2476475 - CVE-2026-8391 firefox: thunderbird: Other issue in the JavaScript Engine component BZ - 2476492 - CVE-2026-8401 firefox: thunderbird: Sandbox escape in the Profile Backup component BZ - 2479839 - CVE-2026-8956 firefox: Integer overflow in the Networking: JAR component BZ - 2479840 - CVE-2026-8975 firefox: Memory safety bugs fixed in Firefox ESR 115.36, Firefox ESR 140.11 and Firefox 151 BZ - 2479842 - CVE-2026-8955 firefox: thunderbird: Privilege escalation in the DOM: Workers component BZ - 2479846 - CVE-2026-8968 firefox: Denial-of-service due to invalid pointer in the Audio/Video: Web Codecs component BZ - 2479847 - CVE-2026-8954 firefox: Incorrect boundary conditions, integer overflow in the Audio/Video component BZ - 2479848 - CVE-2026-8958 firefox: Information disclosure, sandbox escape in the Security: Process Sandboxing component BZ - 2479849 - CVE-2026-8946 firefox: thunderbird: Incorrect boundary conditions in the Audio/Video: Web Codecs component BZ - 2479852 - CVE-2026-8970 firefox: Privilege escalation in the Security component BZ - 2479853 - CVE-2026-8950 firefox: Same-origin policy bypass in the Networking: HTTP component BZ - 2479855 - CVE-2026-8974 firefox: Memory safety bugs fixed in Firefox ESR 140.11 and Firefox 151 BZ - 2479860 - CVE-2026-8953 firefox: Sandbox escape due to use-after-free in the Disability Access APIs component BZ - 2479871 - CVE-2026-8961 firefox: Spoofing issue in the Form Autofill component BZ - 2479873 - CVE-2026-8947 firefox: thunderbird: Use-after-free in the DOM: Bindings (WebIDL) component BZ - 2479876 - CVE-2026-8962 firefox: Mitigation bypass in the DOM: Security component BZ - 2479880 - CVE-2026-8957 firefox: Privilege escalation in the Enterprise Policies component CVEs CVE-2026-8388 CVE-2026-8391 CVE-2026-8401 CVE-2026-8946 CVE-2026-8947 CVE-2026-8950 CVE-2026-8953 CVE-2026-8954 CVE-2026-8955 CVE-2026-8956 CVE-2026-8957 CVE-2026-8958 CVE-2026-8961 CVE-2026-8962 CVE-2026-8968 CVE-2026-8970 CVE-2026-8974 CVE-2026-8975 References https://access.redhat.com/security/updates/classification/#important Note: More recent versions of these packages may be available. Click a package name for more details. Red Hat Enterprise Linux Server - AUS 9.2 SRPM firefox-140.11.0-1.el9_2.src.rpm SHA-256: 7037926ea9a6b2ddfcdc7381f94dcc552b7b1dcac211175a161b8dc755d13d4f x86_64 firefox-140.11.0-1.el9_2.x86_64.rpm SHA-256: a6fd6376db7338ea6f794e87104fd4b0c65e3dae82d78511782fdba622196d33 firefox-debuginfo-140.11.0-1.el9_2.x86_64.rpm SHA-256: 8325da74b312644e5ce5b1700766b26744d300b6c6fe86b5c039e50e18819ab7 firefox-debugsource-140.11.0-1.el9_2.x86_64.rpm SHA-256: 79f63671cb2dc663ef7be0b1e9e21eab3ee7293097e0b145e7ebe18a663bd399 firefox-x11-140.11.0-1.el9_2.x86_64.rpm SHA-256: 5a83dac4804c25592b7185f09e64a08860c9a742740d9add22bd9db25265c666 Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 9.2 SRPM firefox-140.11.0-1.el9_2.src.rpm SHA-256: 7037926ea9a6b2ddfcdc7381f94dcc552b7b1dcac211175a161b8dc755d13d4f ppc64le firefox-140.11.0-1.el9_2.ppc64le.rpm SHA-256: 8a82cafd37802ebfd0fc72aa511956e3dc036f6bf69ca39c73a32c1a4571a059 firefox-debuginfo-140.11.0-1.el9_2.ppc64le.rpm SHA-256: a04933944a8ff7ae4fdc921a42aa691acacb3521df1ac37b5c8691f7bd2412cb firefox-debugsource-140.11.0-1.el9_2.ppc64le.rpm SHA-256: 2a6864517bec658c815dd98f563ef665748e2bc2ee5234aa377f4138a1a09063 firefox-x11-140.11.0-1.el9_2.ppc64le.rpm SHA-256: 23a2d438784e69b9bf423800952275c789b40ea8cf1cb3f817bfaac404aa04c0 Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 9.2 SRPM firefox-140.11.0-1.el9_2.src.rpm SHA-256: 7037926ea9a6b2ddfcdc7381f94dcc552b7b1dcac211175a161b8dc755d13d4f x86_64 firefox-140.11.0-1.el9_2.x86_64.rpm SHA-256: a6fd6376db7338ea6f794e87104fd4b0c65e3dae82d78511782fdba622196d33 firefox-debuginfo-140.11.0-1.el9_2.x86_64.rpm SHA-256: 8325da74b312644e5ce5b1700766b26744d300b6c6fe86b5c039e50e18819ab7 firefox-debugsource-140.11.0-1.el9_2.x86_64.rpm SHA-256: 79f63671cb2dc663ef7be0b1e9e21eab3ee7293097e0b145e7ebe18a663bd399 firefox-x11-140.11.0-1.el9_2.x86_64.rpm SHA-256: 5a83dac4804c25592b7185f09e64a08860c9a742740d9add22bd9db25265c666 Red Hat Enterprise Linux for ARM 64 - 4 years of updates 9.2 SRPM firefox-140.11.0-1.el9_2.src.rpm SHA-256: 7037926ea9a6b2ddfcdc7381f94dcc552b7b1dcac211175a161b8dc755d13d4f aarch64 firefox-140.11.0-1.el9_2.aarch64.rpm SHA-256: e0870d27e32005a717ece0e41a04e86ef05bcac2883a65c81ab392c882de6b66 firefox-debuginfo-140.11.0-1.el9_2.aarch64.rpm SHA-256: 8e027152464048a28103c7ab58c89084ab5f7ca1d45635fcc921a0a8f360f771 firefox-debugsource-140.11.0-1.el9_2.aarch64.rpm SHA-256: 470c44907f93b9a36f4a3a55041a2f6d700bd91e6de29dfd9f6fc19555568c19 firefox-x11-140.11.0-1.el9_2.aarch64.rpm SHA-256: 7af05cc586120698952d8e877f24ef90deabc3582581d18e9725fef2dddf2570 Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 9.2 SRPM firefox-140.11.0-1.el9_2.src.rpm SHA-256: 7037926ea9a6b2ddfcdc7381f94dcc552b7b1dcac211175a161b8dc755d13d4f s390x firefox-140.11.0-1.el9_2.s390x.rpm SHA-256: bf4725ba62c83e7d8a28d9719684e891df7a61f09dac6df8f31134a40e9f10c5 firefox-debuginfo-140.11.0-1.el9_2.s390x.rpm SHA-256: 9013a93f9f5908dde8f4c7c13b169c5418c8bec2e8aaa64351a8bab8a7ee4885 firefox-debugsource-140.11.0-1.el9_2.s390x.rpm SHA-256: 252eb9356120169fdcb27a3e4d81f7436330e831d14f2a9d83b5239dd146ce29 firefox-x11-140.11.0-1.el9_2.s390x.rpm SHA-256: 4ed4080706db8317387963b78fdd8f61ffaddca2267df3fc950cc8e2aa6e42fe Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 9.2 SRPM firefox-140.11.0-1.el9_2.src.rpm SHA-256: 7037926ea9a6b2ddfcdc7381f94dcc552b7b1dcac211175a161b8dc755d13d4f x86_64 firefox-140.11.0-1.el9_2.x86_64.rpm SHA-256: a6fd6376db7338ea6f794e87104fd4b0c65e3dae82d78511782fdba622196d33 firefox-debuginfo-140.11.0-1.el9_2.x86_64.rpm SHA-256: 8325da74b312644e5ce5b1700766b26744d300b6c6fe86b5c039e50e18819ab7 firefox-debugsource-140.11.0-1.el9_2.x86_64.rpm SHA-256: 79f63671cb2dc663ef7be0b1e9e21eab3ee7293097e0b145e7ebe18a663bd399 firefox-x11-140.11.0-1.el9_2.x86_64.rpm SHA-256: 5a83dac4804c25592b7185f09e64a08860c9a742740d9add22bd9db25265c666 Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle 9.2 SRPM firefox-140.11.0-1.el9_2.src.rpm SHA-256: 7037926ea9a6b2ddfcdc7381f94dcc552b7b1dcac211175a161b8dc755d13d4f aarch64 firefox-140.11.0-1.el9_2.aarch64.rpm SHA-256: e0870d27e32005a717ece0e41a04e86ef05bcac2883a65c81ab392c