CVE-2026-92066: mozilla firefox, mozilla thunderbird

CVSS 9.8 (critical) · published 2026-09-15

Sandbox escape in the Profile Backup component. This vulnerability was fixed in Firefox 156 and Thunderbird 156.

Affected products (NVD): mozilla firefox, mozilla thunderbird

Fixed in (NVD): 156.0.0, 156.0

Weakness: CWE-693

Source: NVD CVE-2026-92066

References

• https://bugzilla.mozilla.org/show_bug.cgi?id=2058093
• https://www.mozilla.org/security/advisories/mfsa2026-90/
• https://www.mozilla.org/security/advisories/mfsa2026-94/

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