Critical severity · published Sep 15, 2026
CVE-2026-92035
Sandbox escape due to incorrect boundary conditions in the Graphics component
9.6
CVSS
0.3%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 26% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FI
Firefox · Mozilla
before 115.42.0; 116.0 before 140.17.0; 141.0 before 153.3.0; 154.0.0 before 156.0.0 · source: NVD
TH
Thunderbird · Mozilla
before 140.17.0; 141.0 before 153.3.0; 154.0 before 156.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-92035
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-92035
bugzilla.mozilla.org
https://bugzilla.mozilla.org/show_bug.cgi?id=2061245
www.mozilla.org
https://www.mozilla.org/security/advisories/mfsa2026-102/
www.mozilla.org
https://www.mozilla.org/security/advisories/mfsa2026-90/
www.mozilla.org
https://www.mozilla.org/security/advisories/mfsa2026-93/
www.mozilla.org
https://www.mozilla.org/security/advisories/mfsa2026-94/
www.mozilla.org
https://www.mozilla.org/security/advisories/mfsa2026-96/
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