{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-118021", "assignerOrgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "state": "PUBLISHED", "assignerShortName": "mozilla", "dateReserved": "2026-10-27T14:06:03.867Z", "datePublished": "2026-10-27T14:06:04.037Z", "dateUpdated": "2026-10-27T18:18:11.169Z"}, "containers": {"cna": {"affected": [{"product": "Firefox", "vendor": "Mozilla", "versions": [{"status": "unaffected", "version": "159", "lessThanOrEqual": "*", "versionType": "rpm"}]}, {"product": "Thunderbird", "vendor": "Mozilla", "versions": [{"status": "unaffected", "version": "159", "lessThanOrEqual": "*", "versionType": "rpm"}]}], "descriptions": [{"lang": "en", "value": "Sandbox escape due to use-after-free in the XPCOM component. This vulnerability was fixed in Firefox 159 and Thunderbird 159.", "supportingMedia": [{"type": "text/html", "base64": false, "value": "Sandbox escape due to use-after-free in the XPCOM component. This vulnerability was fixed in Firefox 159 and Thunderbird 159."}]}], "title": "Sandbox escape due to use-after-free in the XPCOM component", "references": [{"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2076695"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-118/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-121/"}], "credits": [{"lang": "en", "value": "Mozilla"}], "providerMetadata": {"orgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "shortName": "mozilla", "dateUpdated": "2026-10-27T18:18:11.169Z"}}}}

{}

{"affected": [{"affectedData": [{"product": "Firefox", "vendor": "Mozilla", "versions": [{"lessThanOrEqual": "*", "status": "unaffected", "version": "159", "versionType": "rpm"}]}, {"product": "Thunderbird", "vendor": "Mozilla", "versions": [{"lessThanOrEqual": "*", "status": "unaffected", "version": "159", "versionType": "rpm"}]}], "source": "security@mozilla.org"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Sandbox escape due to use-after-free in the XPCOM component. This vulnerability was fixed in Firefox 159 and Thunderbird 159."}], "id": "CVE-2026-118021", "lastModified": "2026-10-27T19:17:27.850", "metrics": {}, "published": "2026-10-27T14:16:59.887", "references": [{"source": "security@mozilla.org", "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2076695"}, {"source": "security@mozilla.org", "url": "https://www.mozilla.org/security/advisories/mfsa2026-118/"}, {"source": "security@mozilla.org", "url": "https://www.mozilla.org/security/advisories/mfsa2026-121/"}], "sourceIdentifier": "security@mozilla.org", "vulnStatus": "Deferred"}

{"bugzilla": {"description": "firefox: firefox: Sandbox escape via use-after-free in XPCOM", "id": "2562042", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2562042"}, "csaw": false, "cwe": "CWE-825", "details": ["Sandbox escape due to use-after-free in the XPCOM component. This vulnerability was fixed in Firefox 159 and Thunderbird 159.", "A flaw was found in Firefox. A use-after-free vulnerability in the Cross-Platform Component Object Model (XPCOM) component allows an attacker to achieve a sandbox escape. An attacker could exploit this memory corruption issue to break out of the browser's restricted security environment (sandbox) and execute arbitrary code on the host system."], "name": "CVE-2026-118021", "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: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": "2026-10-27T14:06:04Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-118021\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-118021\nhttps://bugzilla.mozilla.org/show_bug.cgi?id=2076695\nhttps://www.mozilla.org/security/advisories/mfsa2026-118/"], "threat_severity": "Important"}