{"id":"CVE-2026-8950","published":"2026-05-19T12:29:42Z","modified":"2026-05-19T17:10:48Z","title":"Same-origin policy bypass in the Networking: HTTP component","vendor":"Mozilla","product":"Firefox","tier":"tail","description":{"text":"Same-origin policy bypass in the Networking: HTTP component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.","provenance":"source","from":"CVE.org"},"cvss":{"score":9.3,"severity":"CRITICAL","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N","provenance":"source","from":"CISA ADP Vulnrichment"},"epss":{"score":0.00194,"percentile":0.09058,"provenance":"source"},"cwes":[{"id":"CWE-346","name":"Origin Validation Error"}],"references":[{"url":"https://bugzilla.mozilla.org/show_bug.cgi?id=1965430","tags":[]},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-46/","tags":[]},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-48/","tags":[]},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-50/","tags":[]},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-51/","tags":[]}],"priority":{"score":8.3,"factors":[{"name":"EPSS percentile","points":1.81},{"name":"CVSS severity","points":6.51}]},"vendorSlug":"mozilla","euvd":{"id":"EUVD-2026-30898","exploited":false,"provenance":"source"},"lineage":{"familyId":"fam-class-mozilla-firefox-cwe-346"}}