CVE-2026-74960

Description

Site isolation issue in the WebExtensions component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, and Firefox ESR 153.1.

References

• 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/