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.

The version of Thunderbird installed on the remote macOS or Mac OS X host is prior to 140.16. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2026-95 advisory.

  - 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, and Thunderbird 140.16. (CVE-2026-92020)

  - A maliciously constructed mail header could lead to multiple fields being parsed as one, or potential     memory safety violations. (CVE-2026-92238)

  - A maliciously constructed IMAP line could cause an out-of-bounds buffer read. (CVE-2026-92239)

  - A malicious or compromised IMAP server can trigger an out-of-bounds read in the IMAP response parser by     sending an untagged ' ID' response, crashing Thunderbird. The affected parsing path is reachable before     authentication. (CVE-2026-92240)

  - 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, and Thunderbird 140.16. (CVE-2026-92005)

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 140.16. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2026-95 advisory.

  - 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, and Thunderbird 140.16. (CVE-2026-92020)

  - A maliciously constructed mail header could lead to multiple fields being parsed as one, or potential     memory safety violations. (CVE-2026-92238)

  - A maliciously constructed IMAP line could cause an out-of-bounds buffer read. (CVE-2026-92239)

  - A malicious or compromised IMAP server can trigger an out-of-bounds read in the IMAP response parser by     sending an untagged ' ID' response, crashing Thunderbird. The affected parsing path is reachable before     authentication. (CVE-2026-92240)

  - 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, and Thunderbird 140.16. (CVE-2026-92005)

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 ESR installed on the remote Windows host is prior to 140.16. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2026-92 advisory.

  - 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, and Firefox ESR 153.3.
    (CVE-2026-92020)

  - Privilege escalation in the DOM: Service Workers component. This vulnerability was fixed in Firefox 156,     Firefox ESR 115.41, Firefox ESR 140.16, and Firefox ESR 153.3. (CVE-2026-92017)

  - Use-after-free in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 156,     Firefox ESR 140.16, and Firefox ESR 153.3. (CVE-2026-92005)

  - 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, and Firefox ESR 153.3.
    (CVE-2026-92006, CVE-2026-92007, CVE-2026-92008, CVE-2026-92009, CVE-2026-92010, CVE-2026-92011,     CVE-2026-92012, CVE-2026-92013)

  - Privilege escalation due to incorrect boundary conditions in the Graphics component. This vulnerability     was fixed in Firefox ESR 115.41 and Firefox ESR 140.16. (CVE-2026-92014)

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 ESR installed on the remote macOS or Mac OS X host is prior to 140.16. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2026-92 advisory.

  - 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, and Firefox ESR 153.3.
    (CVE-2026-92020)

  - Privilege escalation in the DOM: Service Workers component. This vulnerability was fixed in Firefox 156,     Firefox ESR 115.41, Firefox ESR 140.16, and Firefox ESR 153.3. (CVE-2026-92017)

  - Use-after-free in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 156,     Firefox ESR 140.16, and Firefox ESR 153.3. (CVE-2026-92005)

  - 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, and Firefox ESR 153.3.
    (CVE-2026-92006, CVE-2026-92007, CVE-2026-92008, CVE-2026-92009, CVE-2026-92010, CVE-2026-92011,     CVE-2026-92012, CVE-2026-92013)

  - Privilege escalation due to incorrect boundary conditions in the Graphics component. This vulnerability     was fixed in Firefox ESR 115.41 and Firefox ESR 140.16. (CVE-2026-92014)

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 ESR installed on the remote Windows host is prior to 115.41. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2026-91 advisory.

  - Privilege escalation in the WebExtensions component. This vulnerability was fixed in Firefox 156, Firefox     ESR 115.41, Firefox ESR 140.16, and Firefox ESR 153.3. (CVE-2026-92015)

  - 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, and Firefox ESR 153.3.
    (CVE-2026-92006, CVE-2026-92007, CVE-2026-92008, CVE-2026-92009, CVE-2026-92010, CVE-2026-92011,     CVE-2026-92012, CVE-2026-92013)

  - Privilege escalation due to incorrect boundary conditions in the Graphics component. This vulnerability     was fixed in Firefox ESR 115.41 and Firefox ESR 140.16. (CVE-2026-92014)

  - Sandbox escape in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 156, Firefox ESR     115.41, Firefox ESR 140.16, and Firefox ESR 153.3. (CVE-2026-92018)

  - Mitigation bypass in the Remote Settings Client component. This vulnerability was fixed in Firefox 156,     Firefox ESR 115.41, Firefox ESR 140.16, and Firefox ESR 153.3. (CVE-2026-92019)

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 ESR installed on the remote macOS or Mac OS X host is prior to 115.41. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2026-91 advisory.

  - Privilege escalation in the WebExtensions component. This vulnerability was fixed in Firefox 156, Firefox     ESR 115.41, Firefox ESR 140.16, and Firefox ESR 153.3. (CVE-2026-92015)

  - 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, and Firefox ESR 153.3.
    (CVE-2026-92006, CVE-2026-92007, CVE-2026-92008, CVE-2026-92009, CVE-2026-92010, CVE-2026-92011,     CVE-2026-92012, CVE-2026-92013)

  - Privilege escalation due to incorrect boundary conditions in the Graphics component. This vulnerability     was fixed in Firefox ESR 115.41 and Firefox ESR 140.16. (CVE-2026-92014)

  - Sandbox escape in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 156, Firefox ESR     115.41, Firefox ESR 140.16, and Firefox ESR 153.3. (CVE-2026-92018)

  - Mitigation bypass in the Remote Settings Client component. This vulnerability was fixed in Firefox 156,     Firefox ESR 115.41, Firefox ESR 140.16, and Firefox ESR 153.3. (CVE-2026-92019)

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
346178	Mozilla Thunderbird < 140.16	Nessus	MacOS X Local Security Checks	Local	high
346177	Mozilla Thunderbird < 140.16	Nessus	Windows	Local	high
345907	Mozilla Firefox ESR < 140.16	Nessus	Windows	Local	high
345906	Mozilla Firefox ESR < 140.16	Nessus	MacOS X Local Security Checks	Local	high
345902	Mozilla Firefox ESR < 115.41	Nessus	Windows	Local	critical
345900	Mozilla Firefox ESR < 115.41	Nessus	MacOS X Local Security Checks	Local	critical

Detections

Analytics

CVE-2026-92014

high

Tenable Plugins

high

high

high

high

critical

critical