high8.1
CVE-2026-74960
Site isolation issue in the WebExtensions component.
Impact
Site isolation issue in the WebExtensions component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Mozilla | Firefox | before 140.14.0 from 141.0 before 153.1.0 |
| Mozilla | Thunderbird | before 140.14.0 from 141.0 before 153.1.0 |
Weakness classification
References
- NVD record
- CVE.org record
- https://bugzilla.mozilla.org/show_bug.cgi?id=2049148
- https://www.mozilla.org/security/advisories/mfsa2026-74/
- 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/