CVE-2026-74986

Description

Site isolation issue in the CSS Parsing and Computation component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.

Affected Platforms

Weakness Type

Unknown

References

• https://bugzilla.mozilla.org/show_bug.cgi?id=2060048
• https://www.mozilla.org/security/advisories/mfsa2026-74/
• https://www.mozilla.org/security/advisories/mfsa2026-77/
• https://www.mozilla.org/security/advisories/mfsa2026-78/
• https://www.mozilla.org/security/advisories/mfsa2026-80/