CVE-2026-12304
Same-origin policy bypass in the Networking: Cookies component
CVSS Score
9.1
EPSS Score
0.0%
EPSS Percentile
0th
Same-origin policy bypass in the Networking: Cookies component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.
| Vendor | mozilla |
| Product | firefox |
| Ecosystems | |
| Industries | Technology |
| Published | Jun 16, 2026 |
| Last Updated | Jun 16, 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=2034944 mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-57/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-58/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-60/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-61/
Credits
Yaqoub Aldurayhim