7.5highHigh
CVE-2026-74934
Mozilla Firefox
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.
Exploitation status
- A vendor advisory or patch reference has been published.
What the metrics mean
- It is reachable over a network, without needing local access.
- For an attacker who can reach it, exploitation depends on conditions outside the attacker's control.
- To exploit it, no account is needed.
- Beyond that, someone has to be persuaded to take an action first.
Scoring
- CVSS
- 7.5 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H- Weakness
- CWE-200
- Assigned by
- security@mozilla.org
Dates
- Published
- 2026-08-18
- Last modified
- 2026-08-24
- Sources
- NVD
Affected products
- Mozilla Firefox- 115.39.0, 116.0 - 140.14.0, 141.0 - 153.1.0
- Mozilla Thunderbird- 140.14.0, 141.0 - 153.1.0
As listed in the NVD configuration data. Not a statement about your estate.
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=2050584
- https://www.mozilla.org/security/advisories/mfsa2026-74/
- https://www.mozilla.org/security/advisories/mfsa2026-75/
- https://www.mozilla.org/security/advisories/mfsa2026-76/
- https://www.mozilla.org/security/advisories/mfsa2026-77/
- https://www.mozilla.org/security/advisories/mfsa2026-78/
- https://www.mozilla.org/security/advisories/mfsa2026-79/
- https://www.mozilla.org/security/advisories/mfsa2026-80/