CVE-2026-92035: mozilla firefox, mozilla thunderbird

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

Sandbox escape due to incorrect boundary conditions in the Graphics component. This vulnerability was fixed in Thunderbird 140.17, Firefox 156, Firefox ESR 153.3, Thunderbird 156, Thunderbird 153.3, Firefox ESR 115.42, and Firefox ESR 140.17.

Affected products (NVD): mozilla firefox, mozilla thunderbird

Fixed in (NVD): 115.42.0, 140.17.0, 153.3.0, 156.0.0, 156.0

Weakness: CWE-119

Source: NVD CVE-2026-92035

References

• https://bugzilla.mozilla.org/show_bug.cgi?id=2061245
• https://www.mozilla.org/security/advisories/mfsa2026-102/
• 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/
• https://www.mozilla.org/security/advisories/mfsa2026-98/
• https://www.mozilla.org/security/advisories/mfsa2026-99/

Check your software

Connect an AI agent to the FixLane MCP server or ask the Telegram bot to check what you have installed against incidents with a verified fixed version.