{"id":"CVE-2026-100818","title":"Sandbox escape due to use-after-free in the Widget: Gtk component","summary":"Sandbox escape due to use-after-free in the Widget: Gtk component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17.","severity":"critical","cvss":9.6,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H","cwe":["CWE-416"],"vendor":"Mozilla","product":"Firefox","affected":["Firefox"],"published":"2026-09-29","updated":"2026-09-29","sourceUpdated":"2026-09-29T14:17:17.550","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-100818","references":[{"url":"https://bugzilla.mozilla.org/show_bug.cgi?id=2069399","label":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-100/","label":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-97/","label":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-99/","label":"security@mozilla.org"}],"tags":["nvd","cve.org"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-09-29T13:13:15.417892Z"},"ingestedAt":"2026-09-29T13:34:31.675Z","slug":"CVE-2026-100818","body":"## Overview\n\nSandbox escape due to use-after-free in the Widget: Gtk component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"midnight","depthScore":53,"depthScoreParts":{"impact":52.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}