CVE-2026-74962
Site isolation issue in the Networking: Cookies component
CVSS Score
8.1
EPSS Score
0.0%
EPSS Percentile
0th
Site isolation issue in the Networking: Cookies 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.
| Vendor | mozilla |
| Product | firefox |
| Ecosystems | |
| Industries | Technology |
| Published | Aug 18, 2026 |
| Last Updated | Aug 19, 2026 |
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Affected Versions
Mozilla / Firefox
All versions affected Mozilla / Thunderbird
All versions affected References
bugzilla.mozilla.org: https://bugzilla.mozilla.org/show_bug.cgi?id=2050425 mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-74/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-76/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-77/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-78/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-79/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-80/
Credits
Yaqoub Aldurayhim