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OpenAdvisories
High RLSA-2026:71652 28 CVEs

Important: firefox security update

Published Sep 26, 2026 · Updated Sep 26, 2026

Ecosystem: Rocky Linux

Summary

Mozilla Firefox is an open-source web browser, designed for standards compliance, performance, and portability.

Security Fix(es):

* firefox: thunderbird: Use-after-free in the SVG component (CVE-2026-92024)

* firefox: thunderbird: Mitigation bypass in the Remote Settings Client component (CVE-2026-92019)

* firefox: thunderbird: Use-after-free in the Networking component (CVE-2026-92026)

* firefox: thunderbird: Information disclosure in the Graphics: ImageLib component (CVE-2026-92031)

* firefox: thunderbird: Sandbox escape due to invalid pointer in the Graphics component (CVE-2026-92032)

* firefox: thunderbird: Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component (CVE-2026-92010)

* firefox: thunderbird: Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component (CVE-2026-92006)

* firefox: thunderbird: Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component (CVE-2026-92011)

* firefox: thunderbird: Use-after-free in the DOM: Streams component (CVE-2026-92027)

* firefox: thunderbird: Use-after-free in the DOM: Core & HTML component (CVE-2026-92028)

* firefox: thunderbird: Privilege escalation in the WebExtensions component (CVE-2026-92015)

* firefox: thunderbird: Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component (CVE-2026-92013)

* firefox: thunderbird: Use-after-free in the Disability Access APIs component (CVE-2026-92016)

* firefox: thunderbird: Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component (CVE-2026-92012)

* firefox: thunderbird: Use-after-free in the DOM: HTML Parser component (CVE-2026-92022)

* firefox: thunderbird: Privilege escalation due to incorrect boundary conditions in the Graphics component (CVE-2026-92014)

* firefox: thunderbird: Sandbox escape in the DOM: Core & HTML component (CVE-2026-92018)

* firefox: thunderbird: Use-after-free in the JavaScript Engine: JIT component (CVE-2026-92021)

* firefox: thunderbird: Use-after-free in the Audio/Video: Web Codecs component (CVE-2026-92005)

* firefox: thunderbird: Privilege escalation in the DOM: Service Workers component (CVE-2026-92017)

* firefox: thunderbird: Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component (CVE-2026-92009)

* firefox: thunderbird: Privilege escalation due to incorrect boundary conditions in the Graphics: WebRender component (CVE-2026-92020)

* firefox: thunderbird: Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component (CVE-2026-92008)

* firefox: thunderbird: Mitigation bypass in the DOM: Copy & Paste and Drag & Drop component (CVE-2026-92030)

* firefox: thunderbird: Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component (CVE-2026-92007)

* firefox: thunderbird: Use-after-free in the DOM: Navigation component (CVE-2026-92025)

* firefox: thunderbird: Use-after-free in the SVG component (CVE-2026-92029)

* firefox: thunderbird: Use-after-free in the XML component (CVE-2026-92023)

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.

Fixed packages 1

ReleasePackageFixed in
Rocky Linux · 8 firefox 0:140.16.0-1.el8_10

Vulnerabilities 28

  • Critical 9.6
    CVE-2026-92018

    Sandbox escape in the DOM: Core & HTML component

    Sandbox escape in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • Critical 9.6
    CVE-2026-92032

    Sandbox escape due to invalid pointer in the Graphics component

    Sandbox escape due to invalid pointer in the Graphics component. This vulnerability was fixed in Firefox 156, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.8
    CVE-2026-92006

    Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component

    Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.…

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.8
    CVE-2026-92007

    Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component

    Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.…

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.8
    CVE-2026-92008

    Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component

    Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.…

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.8
    CVE-2026-92009

    Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component

    Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.…

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.8
    CVE-2026-92010

    Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component

    Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.…

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.8
    CVE-2026-92011

    Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component

    Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.…

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.8
    CVE-2026-92012

    Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component

    Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.…

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.8
    CVE-2026-92013

    Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component

    Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.…

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.8
    CVE-2026-92014

    Privilege escalation due to incorrect boundary conditions in the Graphics component

    Privilege escalation due to incorrect boundary conditions in the Graphics component. This vulnerability was fixed in Firefox ESR 115.41, Firefox ESR 140.16, and Thunderbird 140.16.

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.8
    CVE-2026-92015

    Privilege escalation in the WebExtensions component

    Privilege escalation in the WebExtensions component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.8
    CVE-2026-92016

    Use-after-free in the Disability Access APIs component

    Use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox 156, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.8
    CVE-2026-92017

    Privilege escalation in the DOM: Service Workers component

    Privilege escalation in the DOM: Service Workers component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.8
    CVE-2026-92020

    Privilege escalation due to incorrect boundary conditions in the Graphics: WebRender component

    Privilege escalation due to incorrect boundary conditions in the Graphics: WebRender component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.8
    CVE-2026-92021

    Use-after-free in the JavaScript Engine: JIT component

    Use-after-free in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox ESR 140.16 and Thunderbird 140.16.

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.8
    CVE-2026-92022

    Use-after-free in the DOM: HTML Parser component

    Use-after-free in the DOM: HTML Parser component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.8
    CVE-2026-92023

    Use-after-free in the XML component

    Use-after-free in the XML component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.8
    CVE-2026-92024

    Use-after-free in the SVG component

    Use-after-free in the SVG component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.8
    CVE-2026-92025

    Use-after-free in the DOM: Navigation component

    Use-after-free in the DOM: Navigation component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.8
    CVE-2026-92026

    Use-after-free in the Networking component

    Use-after-free in the Networking component. This vulnerability was fixed in Firefox 156, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.8
    CVE-2026-92027

    Use-after-free in the DOM: Streams component

    Use-after-free in the DOM: Streams component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.8
    CVE-2026-92028

    Use-after-free in the DOM: Core & HTML component

    Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.8
    CVE-2026-92029

    Use-after-free in the SVG component

    Use-after-free in the SVG component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • High 8.1
    CVE-2026-92019

    Mitigation bypass in the Remote Settings Client component

    Mitigation bypass in the Remote Settings Client component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • Medium 6.5
    CVE-2026-92031

    Information disclosure in the Graphics: ImageLib component

    Information disclosure in the Graphics: ImageLib component. This vulnerability was fixed in Firefox 156, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • Medium 5.4
    CVE-2026-92030

    Mitigation bypass in the DOM: Copy & Paste and Drag & Drop component

    Mitigation bypass in the DOM: Copy & Paste and Drag & Drop component. This vulnerability was fixed in Firefox 156, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu
  • Medium 5.3
    CVE-2026-92005

    Use-after-free in the Audio/Video: Web Codecs component

    Use-after-free in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 156, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

    Mozilla Firefox Thunderbird thunderbird Browsers Debian Ubuntu

References

  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533737
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533740
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533741
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533742
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533743
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533747
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533751
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533753
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533757
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533758
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533760
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533762
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533764
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533769
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533770
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533771
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533773
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533774
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533778
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533779
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533781
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533786
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533790
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533791
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533792
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533793
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533797
  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2533799
  • advisory
    https://access.redhat.com/errata/RHSA-2026:71652