Red Hat Product Errata RHSA-2026:10766 - Security Advisory Issued: 2026-04-27 Updated: 2026-04-27 RHSA-2026:10766 - 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 8. 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: thunderbird: Incorrect boundary conditions in the Libraries component in NSS (CVE-2026-6772) firefox: thunderbird: Use-after-free in the JavaScript Engine component (CVE-2026-6754) firefox: thunderbird: Spoofing issue in the DOM: Core & HTML component (CVE-2026-6762) firefox: thunderbird: Incorrect boundary conditions in the WebRTC component (CVE-2026-6752) firefox: thunderbird: Other issue in the Storage: IndexedDB component (CVE-2026-6770) firefox: thunderbird: Invalid pointer in the JavaScript: WebAssembly component (CVE-2026-6757) firefox: thunderbird: Other issue in the Libraries component in NSS (CVE-2026-6767) firefox: thunderbird: Memory safety bugs fixed in Firefox ESR 140.10, Thunderbird ESR 140.10, Firefox 150 and Thunderbird 150 (CVE-2026-6786) firefox: thunderbird: Incorrect boundary conditions in the WebRTC component (CVE-2026-6753) firefox: thunderbird: Use-after-free in the Widget: Cocoa component (CVE-2026-6759) firefox: thunderbird: Use-after-free in the WebRTC component (CVE-2026-6747) firefox: thunderbird: Information disclosure due to uninitialized memory in the Graphics: Canvas2D component (CVE-2026-6749) firefox: thunderbird: Incorrect boundary conditions in the Libraries component in NSS (CVE-2026-6766) firefox: thunderbird: Privilege escalation in the Networking component (CVE-2026-6761) firefox: thunderbird: Mitigation bypass in the File Handling component (CVE-2026-6763) firefox: thunderbird: Privilege escalation in the Graphics: WebRender component (CVE-2026-6750) firefox: thunderbird: Uninitialized memory in the Audio/Video: Web Codecs component (CVE-2026-6748) firefox: thunderbird: Memory safety bugs fixed in Firefox ESR 115.35, Firefox ESR 140.10, Thunderbird ESR 140.10, Firefox 150 and Thunderbird 150 (CVE-2026-6785) firefox: thunderbird: Mitigation bypass in the DOM: Security component (CVE-2026-6771) firefox: thunderbird: Incorrect boundary conditions in the DOM: Device Interfaces component (CVE-2026-6764) firefox: thunderbird: Information disclosure in the Form Autofill component (CVE-2026-6765) firefox: thunderbird: Privilege escalation in the Debugger component (CVE-2026-6769) firefox: thunderbird: Uninitialized memory in the Audio/Video: Web Codecs component (CVE-2026-6751) firefox: thunderbird: Incorrect boundary conditions in the WebRTC: Networking component (CVE-2026-6776) firefox: thunderbird: Use-after-free in the DOM: Core & HTML component (CVE-2026-6746) 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 for x86_64 8 x86_64 Red Hat Enterprise Linux for IBM z Systems 8 s390x Red Hat Enterprise Linux for Power, little endian 8 ppc64le Red Hat Enterprise Linux for ARM 64 8 aarch64 Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 8.10 x86_64 Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle 8.10 aarch64 Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle 8.10 ppc64le Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle 8.10 s390x Fixes BZ - 2460074 - CVE-2026-6772 firefox: thunderbird: Incorrect boundary conditions in the Libraries component in NSS BZ - 2460075 - CVE-2026-6754 firefox: thunderbird: Use-after-free in the JavaScript Engine component BZ - 2460076 - CVE-2026-6762 firefox: thunderbird: Spoofing issue in the DOM: Core & HTML component BZ - 2460078 - CVE-2026-6752 firefox: thunderbird: Incorrect boundary conditions in the WebRTC component BZ - 2460079 - CVE-2026-6770 firefox: thunderbird: Other issue in the Storage: IndexedDB component BZ - 2460085 - CVE-2026-6757 firefox: thunderbird: Invalid pointer in the JavaScript: WebAssembly component BZ - 2460086 - CVE-2026-6767 firefox: thunderbird: Other issue in the Libraries component in NSS BZ - 2460088 - CVE-2026-6786 firefox: thunderbird: Memory safety bugs fixed in Firefox ESR 140.10, Thunderbird ESR 140.10, Firefox 150 and Thunderbird 150 BZ - 2460092 - CVE-2026-6753 firefox: thunderbird: Incorrect boundary conditions in the WebRTC component BZ - 2460094 - CVE-2026-6759 firefox: thunderbird: Use-after-free in the Widget: Cocoa component BZ - 2460095 - CVE-2026-6747 firefox: thunderbird: Use-after-free in the WebRTC component BZ - 2460096 - CVE-2026-6749 firefox: thunderbird: Information disclosure due to uninitialized memory in the Graphics: Canvas2D component BZ - 2460097 - CVE-2026-6766 firefox: thunderbird: Incorrect boundary conditions in the Libraries component in NSS BZ - 2460099 - CVE-2026-6761 firefox: thunderbird: Privilege escalation in the Networking component BZ - 2460101 - CVE-2026-6763 firefox: thunderbird: Mitigation bypass in the File Handling component BZ - 2460102 - CVE-2026-6750 firefox: thunderbird: Privilege escalation in the Graphics: WebRender component BZ - 2460103 - CVE-2026-6748 firefox: thunderbird: Uninitialized memory in the Audio/Video: Web Codecs component BZ - 2460104 - CVE-2026-6785 firefox: thunderbird: Memory safety bugs fixed in Firefox ESR 115.35, Firefox ESR 140.10, Thunderbird ESR 140.10, Firefox 150 and Thunderbird 150 BZ - 2460105 - CVE-2026-6771 firefox: thunderbird: Mitigation bypass in the DOM: Security component BZ - 2460106 - CVE-2026-6764 firefox: thunderbird: Incorrect boundary conditions in the DOM: Device Interfaces component BZ - 2460107 - CVE-2026-6765 firefox: thunderbird: Information disclosure in the Form Autofill component BZ - 2460108 - CVE-2026-6769 firefox: thunderbird: Privilege escalation in the Debugger component BZ - 2460109 - CVE-2026-6751 firefox: thunderbird: Uninitialized memory in the Audio/Video: Web Codecs component BZ - 2460110 - CVE-2026-6776 firefox: thunderbird: Incorrect boundary conditions in the WebRTC: Networking component BZ - 2460112 - CVE-2026-6746 firefox: thunderbird: Use-after-free in the DOM: Core & HTML component CVEs CVE-2026-6746 CVE-2026-6747 CVE-2026-6748 CVE-2026-6749 CVE-2026-6750 CVE-2026-6751 CVE-2026-6752 CVE-2026-6753 CVE-2026-6754 CVE-2026-6757 CVE-2026-6759 CVE-2026-6761 CVE-2026-6762 CVE-2026-6763 CVE-2026-6764 CVE-2026-6765 CVE-2026-6766 CVE-2026-6767 CVE-2026-6769 CVE-2026-6770 CVE-2026-6771 CVE-2026-6772 CVE-2026-6776 CVE-2026-6785 CVE-2026-6786 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 for x86_64 8 SRPM firefox-140.10.0-1.el8_10.src.rpm SHA-256: e0bbc06acba2dd0ffd73c2240b7d5e9f6219e1c3f42fd0836e4820d07cc42ca7 x86_64 firefox-140.10.0-1.el8_10.x86_64.rpm SHA-256: 889576740e77f098ca1b65ee3baa8af61738c9ad515b52ab6919d9d71d6d4caa firefox-debuginfo-140.10.0-1.el8_10.x86_64.rpm SHA-256: 7b419c204851fbdb81073b7c69879dab168a5259ddd3a03f83a12212ed9cfa8a firefox-debugsource-140.10.0-1.el8_10.x86_64.rpm SHA-256: d910dec53857a67737d0f197c7620f5ddad3eaa76aa6ecde9b96880bfa0ee864 Red Hat Enterprise Linux for IBM z Systems 8 SRPM firefox-140.10.0-1.el8_10.src.rpm SHA-256: e0bbc06acba2dd0ffd73c2240b7d5e9f6219e1c3f42fd0836e4820d07cc42ca7 s390x firefox-140.10.0-1.el8_10.s390x.rpm SHA-256: 904dd642b311fd44b2454af0b4d530cbf519eb6eabf934fcfb17bf8e94dca887 firefox-debuginfo-140.10.0-1.el8_10.s390x.rpm SHA-256: 1c5a415d8e49f5be6beac2129599b5adb11f3c29af7e5eb1c4ba3989ab3ba5e6 firefox-debugsource-140.10.0-1.el8_10.s390x.rpm SHA-256: f22eb6879bc2612d35a541565dcbe588bf62591acfb29d560e5b378f2c1cf801 Red Hat Enterprise Linux for Power, little endian 8 SRPM firefox-140.10.0-1.el8_10.src.rpm SHA-256: e0bbc06acba2dd0ffd73c2240b7d5e9f6219e1c3f42fd0836e4820d07cc42ca7 ppc64le firefox-140.10.0-1.el8_10.ppc64le.rpm SHA-256: 291d2502a8bfac4faaa4d78e1d9dd6aa253d31f6bf475ab6113d73184a522cc0 firefox-debuginfo-140.10.0-1.el8_10.ppc64le.rpm SHA-256: 1a62583f1c07bcaf5dc8ae318894bdfdd07989c4ab15aa2d775bda2e434f2643 firefox-debugsource-140.10.0-1.el8_10.ppc64le.rpm SHA-256: 8d69ba3bcfea96be224ff0ffae4af114cd79706b8646f16783e6455e27450e23 Red Hat Enterprise Linux for ARM 64 8 SRPM firefox-140.10.0-1.el8_10.src.rpm SHA-256: e0bbc06acba2dd0ffd73c2240b7d5e9f6219e1c3f42fd0836e4820d07cc42ca7 aarch64 firefox-140.10.0-1.el8_10.aarch64.rpm SHA-256: 4b4b0954abbd9bfb3943c672ff2b35511a200eac71dddfa1a768b85a2a9de520 firefox-debuginfo-140.10.0-1.el8_10.aarch64.rpm SHA-256: 0e4038950be9297a27226f03792e8372bc32ecdd0a46fda385a26dea93d2ee41 firefox-debugsource-140.10.0-1.el8_10.aarch64.rpm SHA-256: 75efecee0c087cd389016442d695fa22500ae1d320d67513095eee1483cf1f46 Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 8.10 SRPM firefox-140.10.0-1.el8_10.src.rpm SHA-256: e0bbc06acba2dd0ffd73c2240b7d5e9f6219e1c3f42fd0836e4820d07cc42ca7 x86_64 firefox-140.10.0-1.el8_10.x86_64.rpm SHA-256: 889576740e77f098ca1b65ee3baa8af61738c9ad515b52ab6919d9d71d6d4caa firefox-debuginfo-140.10.0-1.el8_10.x86_64.rpm SHA-256: 7b419c204851fbdb81073b7c69879dab168a5259ddd3a03f83a12212ed9cfa8a firefox-debugsource-1