CVE-2026-92071: mozilla firefox, mozilla thunderbird

CVSS 9.6 (critical) · published 2026-09-15

Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component. This vulnerability was fixed in Firefox 156, Firefox ESR 153.3, Thunderbird 156, and Thunderbird 153.3.

Affected products (NVD): mozilla firefox, mozilla thunderbird

Fixed in (NVD): 153.3.0, 156.0.0, 156.0

Weakness: CWE-119

Source: NVD CVE-2026-92071

References

• https://bugzilla.mozilla.org/show_bug.cgi?id=2061231
• https://www.mozilla.org/security/advisories/mfsa2026-90/
• https://www.mozilla.org/security/advisories/mfsa2026-93/
• https://www.mozilla.org/security/advisories/mfsa2026-94/
• https://www.mozilla.org/security/advisories/mfsa2026-96/

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