VulnerabilityAnalyzed
CVE-2026-74934
This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.
HIGH 7.5EPSS 0.16%
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.16%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Site isolation issue in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
- EPSS
- 0.16% probability · 5th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-200, CWE-284, CWE-346
- Affected
- mozilla/firefox · mozilla/thunderbird
- Source
- security@mozilla.org
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=2050584Permissions Required
- https://www.mozilla.org/security/advisories/mfsa2026-74/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-75/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-76/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-77/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-78/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-79/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-80/Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.