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OpenAdvisories
High ALAS2-2026-3880 38 CVEs

Important: thunderbird security update (Amazon Linux 2)

Published Aug 31, 2026 · Updated Aug 31, 2026

Summary

Package updates are available for Amazon Linux 2 that fix the following vulnerabilities: CVE-2026-76957: libexpat before 2.8.4 lacks handler call depth tracking with custom encoding callbacks. Thus, a use-after-free can occur. NOTE: this is similar to CVE-2026-50219, CVE-2026-56131 and CVE-2026-56412. CVE-2026-74990: Internally found bugs present in Thunderbird ESR 140.13, Thunderbird ESR 153.0 and Thunderbird 153. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1. CVE-2026-74988: Internally found bugs present in Thunderbird ESR 153.0 and Thunderbird 153. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1. CVE-2026-74987: Internally found bugs present in Thunderbird ESR 140.13, Thunderbird ESR 153.0 and Thunderbird 153. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1. CVE-2026-74983: Mitigation bypass in the Data Loss Prevention component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1. CVE-2026-74976: JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1. CVE-2026-74974: Same-origin policy bypass in the Graphics: ImageLib component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1. CVE-2026-74973: Race condition, use-after-free in the Graphics component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1. CVE-2026-74972: Information disclosure in the DOM: Push Subscriptions component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1. CVE-2026-74971: Information disclosure in the DOM: UI Events & Focus Handling component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1. CVE-2026-74969: Use-after-free in the Layout: Text and Fonts component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1. CVE-2026-74968: Site isolation issue in the Graphics: WebRender component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1. CVE-2026-74967: Same-origin policy bypass in the Audio/Video: Playback component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1. CVE-2026-74965: Privilege escalation in the Shell Integration component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1. CVE-2026-74964: Integer overflow in the Graphics component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1. CVE-2026-74963: Same-origin policy bypass in the Networking: Cookies component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1. CVE-2026-74962: Site isolation issue in the Networking: Cookies component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1. CVE-2026-74960: Site isolation issue in the WebExtensions component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1. CVE-2026-74959: Mitigation bypass in the Storage: Cache API component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1. CVE-2026-74957: Mitigation bypass in the Safe Browsing component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1. CVE-2026-74953: Privilege escalation in the Networking: Cookies component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, and Firefox ESR 153.1. CVE-2026-74950: Privilege escalation in the Downloads API component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1. CVE-2026-74949: Privilege escalation due to use-after-free in the Graphics: Canvas2D component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, and Firefox ESR 153.1. CVE-2026-74948: Information disclosure in the Graphics component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, and Firefox ESR 153.1. CVE-2026-74946: Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, and Firefox ESR 153.1. CVE-2026-7

Fixed packages 1

ReleasePackageFixed in
Amazon Linux · 2 thunderbird 0:140.14.0-1.amzn2.0.1

Vulnerabilities 38

  • Critical 9.8
    CVE-2026-74936 Public exploit

    Use-after-free in the JavaScript: WebAssembly component

    Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • Critical 9.8

    Use-after-free in the Graphics: Text component

    Use-after-free in the Graphics: Text component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • Critical 9.8
    CVE-2026-74943 Public exploit

    Use-after-free in the Graphics: ImageLib component

    Use-after-free in the Graphics: ImageLib component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • Critical 9.8

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

    Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • Critical 9.8

    Integer overflow in the Graphics component

    Integer overflow in the Graphics component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • Critical 9.8

    Internally found bugs fixed in Firefox ESR 140.14, Firefox ESR 153.1 and Firefox 154

    Internally found bugs present in Firefox ESR 140.13, Firefox ESR 153.0 and Firefox 153. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited.…

  • Critical 9.8

    Internally found bugs fixed in Firefox ESR 153.1 and Firefox 154

    Internally found bugs present in Firefox ESR 153.0 and Firefox 153. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability …

  • Critical 9.8

    Internally found bugs fixed in Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1 and Firefox 154

    Internally found bugs present in Firefox ESR 115.38, Firefox ESR 140.13, Firefox ESR 153.0 and Firefox 153. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could …

  • Critical 9.1

    Mitigation bypass in the JavaScript: GC component

    Mitigation bypass in the JavaScript: GC component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.

  • Critical 9.1

    Mitigation bypass in the Storage: Cache API component

    Mitigation bypass in the Storage: Cache API component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • High 8.8

    Privilege escalation in the DOM: Networking component

    Privilege escalation in the DOM: Networking component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • High 8.8
    CVE-2026-74939 Public exploit

    Privilege escalation in the DOM: Navigation component

    Privilege escalation in the DOM: Navigation component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • High 8.8

    Privilege escalation in the Graphics: CanvasWebGL component

    Privilege escalation in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • High 8.8

    Privilege escalation in the Remote Settings Client component

    Privilege escalation in the Remote Settings Client component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • High 8.8

    Information disclosure due to incorrect boundary conditions in the Graphics: CanvasWebGL component

    Information disclosure due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 15…

  • High 8.8

    Use-after-free in the Graphics: Canvas2D component

    Use-after-free in the Graphics: Canvas2D component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • High 8.8

    Privilege escalation in the Downloads API component

    Privilege escalation in the Downloads API component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.

  • High 8.8

    Privilege escalation in the Networking: Cookies component

    Privilege escalation in the Networking: Cookies component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • High 8.8

    Privilege escalation in the Shell Integration component

    Privilege escalation in the Shell Integration component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • High 8.8

    Race condition, use-after-free in the Layout: Text and Fonts component

    Race condition, use-after-free in the Layout: Text and Fonts component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • High 8.1

    Mitigation bypass in the Safe Browsing component

    Mitigation bypass in the Safe Browsing component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • High 8.1

    Site isolation issue in the WebExtensions component

    Site isolation issue in the WebExtensions component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • High 8.1

    Site isolation issue in the Networking: Cookies component

    Site isolation issue in the Networking: Cookies component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • High 8.1

    Mitigation bypass in the Data Loss Prevention component

    Mitigation bypass in the Data Loss Prevention component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • High 7.5

    Expat Denial of Service via storeAtts() Quadratic Complexity

    Expat through 2.8.3 contains a denial of service vulnerability caused by quadratic algorithmic complexity in the storeAtts() function in xmlparse.c, where processing N specified attributes with non-normalized values triggers an O(N^2) linear scan of elementTy…

  • High 7.5

    Site isolation issue in the Graphics: CanvasWebGL component

    Site isolation issue in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • Medium 6.5
    CVE-2026-74945 Public exploit

    Information disclosure in the Graphics: Text component

    Information disclosure in the Graphics: Text component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • Medium 6.5

    Information disclosure in the Graphics component

    Information disclosure in the Graphics component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • Medium 6.5

    JIT miscompilation in the JavaScript Engine: JIT component

    JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • Medium 6.2

    libexpat before 2.8.3 has an out-of-bounds read and resultant infinite loop because low surrogates are treated the same…

  • Medium 5.4

    Same-origin policy bypass in the Networking: Cookies component

    Same-origin policy bypass in the Networking: Cookies component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • Medium 5.4

    Same-origin policy bypass in the Audio/Video: Playback component

    Same-origin policy bypass in the Audio/Video: Playback component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • Medium 5.4

    Site isolation issue in the Graphics: WebRender component

    Site isolation issue in the Graphics: WebRender component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.

  • Medium 5.4

    Same-origin policy bypass in the Graphics: ImageLib component

    Same-origin policy bypass in the Graphics: ImageLib component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • Medium 4.9

    libexpat before 2.8.4 lacks handler call depth tracking with custom encoding callbacks. Thus, a use-after-free can occu…

  • Medium 4.3

    Information disclosure in the DOM: UI Events & Focus Handling component

    Information disclosure in the DOM: UI Events & Focus Handling component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • Medium 4.3

    Information disclosure in the DOM: Push Subscriptions component

    Information disclosure in the DOM: Push Subscriptions component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

  • Medium 4.2

    Race condition, use-after-free in the Graphics component

    Race condition, use-after-free in the Graphics component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

References

  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-66046.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-72522.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74934.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74935.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74936.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74938.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74939.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74940.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74941.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74942.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74943.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74944.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74945.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74946.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74948.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74949.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74950.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74953.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74957.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74959.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74960.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74962.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74963.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74964.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74965.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74967.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74968.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74969.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74971.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-74972.html