VulnerabilityModified
CVE-2026-12312
This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.
HIGH 7.5EPSS 0.25%
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.25%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Memory safety bug fixed in Firefox 152. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- EPSS
- 0.25% probability · 17th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-119
- Affected
- mozilla/firefox · mozilla/thunderbird
- Source
- security@mozilla.org
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=2040383Permissions Required
- https://www.mozilla.org/security/advisories/mfsa2026-57/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-58/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-60/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-61/Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.