{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-117920", "assignerOrgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "state": "PUBLISHED", "assignerShortName": "mozilla", "dateReserved": "2026-10-27T14:05:25.590Z", "datePublished": "2026-10-27T14:05:25.763Z", "dateUpdated": "2026-10-27T18:29:00.904Z"}, "containers": {"cna": {"affected": [{"product": "Firefox", "vendor": "Mozilla", "versions": [{"status": "unaffected", "version": "153.6", "lessThanOrEqual": "153.*", "versionType": "rpm"}, {"status": "unaffected", "version": "159", "lessThanOrEqual": "*", "versionType": "rpm"}]}, {"product": "Thunderbird", "vendor": "Mozilla", "versions": [{"status": "unaffected", "version": "153.6", "lessThanOrEqual": "153.*", "versionType": "rpm"}, {"status": "unaffected", "version": "159", "lessThanOrEqual": "*", "versionType": "rpm"}]}], "descriptions": [{"lang": "en", "value": "Use-after-free in the DOM: HTML Parser component. This vulnerability was fixed in Firefox 159, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.", "supportingMedia": [{"type": "text/html", "base64": false, "value": "Use-after-free in the DOM: HTML Parser component. This vulnerability was fixed in Firefox 159, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6."}]}], "title": "Use-after-free in the DOM: HTML Parser component", "references": [{"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2079681"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-118/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-120/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-121/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-122/"}], "credits": [{"lang": "en", "value": "Mozilla"}], "providerMetadata": {"orgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "shortName": "mozilla", "dateUpdated": "2026-10-27T18:29:00.904Z"}}}}

{}

{"affected": [{"affectedData": [{"product": "Firefox", "vendor": "Mozilla", "versions": [{"lessThanOrEqual": "153.*", "status": "unaffected", "version": "153.6", "versionType": "rpm"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "159", "versionType": "rpm"}]}, {"product": "Thunderbird", "vendor": "Mozilla", "versions": [{"lessThanOrEqual": "153.*", "status": "unaffected", "version": "153.6", "versionType": "rpm"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "159", "versionType": "rpm"}]}], "source": "security@mozilla.org"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Use-after-free in the DOM: HTML Parser component. This vulnerability was fixed in Firefox 159, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6."}], "id": "CVE-2026-117920", "lastModified": "2026-10-27T19:17:17.677", "metrics": {}, "published": "2026-10-27T14:16:47.533", "references": [{"source": "security@mozilla.org", "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2079681"}, {"source": "security@mozilla.org", "url": "https://www.mozilla.org/security/advisories/mfsa2026-118/"}, {"source": "security@mozilla.org", "url": "https://www.mozilla.org/security/advisories/mfsa2026-120/"}, {"source": "security@mozilla.org", "url": "https://www.mozilla.org/security/advisories/mfsa2026-121/"}, {"source": "security@mozilla.org", "url": "https://www.mozilla.org/security/advisories/mfsa2026-122/"}], "sourceIdentifier": "security@mozilla.org", "vulnStatus": "Deferred"}

{"bugzilla": {"description": "firefox: Use-after-free in the DOM: HTML Parser component", "id": "2562183", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2562183"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.5", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-825", "details": ["Use-after-free in the DOM: HTML Parser component. This vulnerability was fixed in Firefox 159, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.", "A flaw was found in Firefox. The Mozilla Foundation's Security Advisory describes the following issue:\nUse-after-free in the DOM: HTML Parser component"], "name": "CVE-2026-117920", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "rhel10/firefox-flatpak", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-10-27T14:05:25Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-117920\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-117920\nhttps://www.mozilla.org/security/advisories/mfsa2026-120/#CVE-2026-117920"], "statement": "Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.", "threat_severity": "Important"}