{"id":"CVE-2026-8964","title":"Spoofing issue in the Popup Blocker component","summary":"Spoofing issue in the Popup Blocker component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","cwe":["CWE-451"],"vendor":"mozilla","product":"firefox","affected":["firefox < 151.0.0","thunderbird < 151.0.0"],"patched":["firefox 151.0.0","thunderbird 151.0.0"],"published":"2026-05-19","updated":"2026-07-23","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-8964","references":[{"url":"https://bugzilla.mozilla.org/show_bug.cgi?id=2025170","label":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-46/","label":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-50/","label":"security@mozilla.org"}],"tags":["nvd"],"epss":0.00302,"epssPercentile":0.23106,"ingestedAt":"2026-07-23T20:19:19.063Z","slug":"CVE-2026-8964","body":"## Overview\n\nSpoofing issue in the Popup Blocker component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.\n\n## Affected\n\n- `firefox < 151.0.0`\n- `thunderbird < 151.0.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `firefox 151.0.0`\n- `thunderbird 151.0.0`","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}