{"id":"CVE-2026-92068","published":"2026-09-15T12:34:29Z","modified":"2026-09-22T15:29:17Z","title":"Site isolation issue in the Reader Mode component","vendor":"Mozilla","product":"Firefox","tier":"tail","description":{"text":"Site isolation issue in the Reader Mode component. This vulnerability was fixed in Firefox 156, Firefox ESR 153.3, Thunderbird 156, and Thunderbird 153.3.","provenance":"source","from":"CVE.org"},"cvss":{"score":5.4,"severity":"MEDIUM","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N","provenance":"source","from":"CISA ADP Vulnrichment"},"epss":{"score":0.00105,"percentile":0.01051,"provenance":"source"},"cwes":[{"id":"CWE-346","name":"Origin Validation Error"}],"references":[{"url":"https://bugzilla.mozilla.org/show_bug.cgi?id=2058790","tags":[]},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-90/","tags":[]},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-93/","tags":[]},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-94/","tags":[]},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-96/","tags":[]}],"priority":{"score":4.0,"factors":[{"name":"EPSS percentile","points":0.21},{"name":"CVSS severity","points":3.78}]},"vendorSlug":"mozilla","euvd":{"id":"EUVD-2026-78453","exploited":false,"provenance":"source"},"lineage":{"familyId":"fam-class-mozilla-firefox-cwe-346"}}