Privilege escalation due to incorrect boundary conditions in the Graphics: WebGPU component. This vulnerability was fixed in Thunderbird 157 and Firefox 157.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - Privilege escalation due to incorrect boundary conditions in the Graphics: WebGPU component. This     vulnerability was fixed in Thunderbird 157 and Firefox 157. (CVE-2026-100764)

Note that Nessus relies on the presence of the package as reported by the vendor.

The version of Thunderbird installed on the remote macOS or Mac OS X host is prior to 157.0. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2026-101 advisory.

  - Use-after-free in the DOM: UI Events & Focus Handling component. This vulnerability was fixed in Firefox     ESR 153.4 and Firefox 157. (CVE-2026-100831)

  - Sandbox escape due to incorrect boundary conditions in the XPCOM component. This vulnerability was fixed     in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. (CVE-2026-100819)

  - An attacker could cause a heap buffer overflow by getting a user to open an email that is greater than or     equal to 2GB in size. (CVE-2026-103500)

  - Incorrect boundary conditions in the Audio/Video: Playback component. This vulnerability was fixed in     Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. (CVE-2026-100756)

  - Use-after-free in the Widget component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157,     Firefox ESR 115.42, and Firefox ESR 140.17. (CVE-2026-100757)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The version of Thunderbird installed on the remote Windows host is prior to 157.0. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2026-101 advisory.

  - Use-after-free in the DOM: UI Events & Focus Handling component. This vulnerability was fixed in Firefox     ESR 153.4 and Firefox 157. (CVE-2026-100831)

  - Sandbox escape due to incorrect boundary conditions in the XPCOM component. This vulnerability was fixed     in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. (CVE-2026-100819)

  - An attacker could cause a heap buffer overflow by getting a user to open an email that is greater than or     equal to 2GB in size. (CVE-2026-103500)

  - Incorrect boundary conditions in the Audio/Video: Playback component. This vulnerability was fixed in     Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. (CVE-2026-100756)

  - Use-after-free in the Widget component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157,     Firefox ESR 115.42, and Firefox ESR 140.17. (CVE-2026-100757)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The version of Firefox installed on the remote macOS or Mac OS X host is prior to 157.0. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2026-97 advisory.

  - Privilege escalation in the Places component. This vulnerability was fixed in Firefox ESR 153.4 and     Firefox 157. (CVE-2026-100824)

  - Sandbox escape due to incorrect boundary conditions in the XPCOM component. This vulnerability was fixed     in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. (CVE-2026-100819)

  - Incorrect boundary conditions in the Audio/Video: Playback component. This vulnerability was fixed in     Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. (CVE-2026-100756)

  - Use-after-free in the Widget component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157,     Firefox ESR 115.42, and Firefox ESR 140.17. (CVE-2026-100757)

  - Sandbox escape in the DOM: Navigation component. This vulnerability was fixed in Firefox ESR 153.4,     Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. (CVE-2026-100758)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The version of Firefox installed on the remote Windows host is prior to 157.0. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2026-97 advisory.

  - Privilege escalation in the Places component. This vulnerability was fixed in Firefox ESR 153.4 and     Firefox 157. (CVE-2026-100824)

  - Sandbox escape due to incorrect boundary conditions in the XPCOM component. This vulnerability was fixed     in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. (CVE-2026-100819)

  - Incorrect boundary conditions in the Audio/Video: Playback component. This vulnerability was fixed in     Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. (CVE-2026-100756)

  - Use-after-free in the Widget component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157,     Firefox ESR 115.42, and Firefox ESR 140.17. (CVE-2026-100757)

  - Sandbox escape in the DOM: Navigation component. This vulnerability was fixed in Firefox ESR 153.4,     Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. (CVE-2026-100758)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Type	Severity
358329	Linux Distros Unpatched Vulnerability : CVE-2026-100764	Nessus	Misc.	Local	high
353287	Mozilla Thunderbird < 157.0	Nessus	MacOS X Local Security Checks	Local	critical
353286	Mozilla Thunderbird < 157.0	Nessus	Windows	Local	critical
351120	Mozilla Firefox < 157.0	Nessus	MacOS X Local Security Checks	Local	critical
351119	Mozilla Firefox < 157.0	Nessus	Windows	Local	critical

Detections

Analytics

CVE-2026-100764

high

Tenable Plugins

high

critical

critical

critical

critical