{"id":"CVE-2026-100809","published":"2026-09-29T12:36:23Z","modified":"2026-10-01T15:31:00Z","title":"Same-origin policy bypass in the DevTools component","vendor":"Mozilla","product":"Firefox","tier":"tail","description":{"text":"Same-origin policy bypass in the DevTools component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 153.4, and Firefox 157.","provenance":"source","from":"CVE.org"},"cvss":{"score":8.1,"severity":"HIGH","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N","provenance":"source","from":"CISA ADP Vulnrichment"},"epss":{"score":0.00153,"percentile":0.04365,"provenance":"source"},"cwes":[{"id":"CWE-346","name":"Origin Validation Error"}],"references":[{"url":"https://bugzilla.mozilla.org/show_bug.cgi?id=2063658","tags":[]},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-100/","tags":[]},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-101/","tags":[]},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-103/","tags":[]},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-97/","tags":[]}],"priority":{"score":6.5,"factors":[{"name":"EPSS percentile","points":0.87},{"name":"CVSS severity","points":5.67}]},"vendorSlug":"mozilla","euvd":{"id":"EUVD-2026-88788","exploited":false,"provenance":"source"},"lineage":{"familyId":"fam-class-mozilla-firefox-cwe-346"}}