{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-84121", "assignerOrgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "state": "PUBLISHED", "assignerShortName": "mozilla", "dateReserved": "2026-09-01T07:25:11.012Z", "datePublished": "2026-09-01T12:18:41.535Z", "dateUpdated": "2026-09-01T12:18:41.535Z"}, "containers": {"cna": {"affected": [{"product": "Firefox", "vendor": "Mozilla", "versions": [{"status": "unaffected", "version": "115.40", "lessThanOrEqual": "115.*", "versionType": "rpm"}, {"status": "unaffected", "version": "140.15", "lessThanOrEqual": "140.*", "versionType": "rpm"}, {"status": "unaffected", "version": "153.2", "lessThanOrEqual": "153.*", "versionType": "rpm"}, {"status": "unaffected", "version": "155", "lessThanOrEqual": "*", "versionType": "rpm"}]}], "descriptions": [{"lang": "en", "value": "Sandbox escape due to use-after-free in the DOM: Security component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, and Firefox ESR 153.2.", "supportingMedia": [{"type": "text/html", "base64": false, "value": "Sandbox escape due to use-after-free in the DOM: Security component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, and Firefox ESR 153.2."}]}], "title": "Sandbox escape due to use-after-free in the DOM: Security component", "references": [{"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2059018"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-82/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-83/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-84/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-85/"}], "credits": [{"lang": "en", "value": "Yaqoub Aldurayhim"}], "providerMetadata": {"orgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "shortName": "mozilla", "dateUpdated": "2026-09-01T12:18:41.535Z"}}}}

{}

{"affected": [{"affectedData": [{"product": "Firefox", "vendor": "Mozilla", "versions": [{"lessThanOrEqual": "115.*", "status": "unaffected", "version": "115.40", "versionType": "rpm"}, {"lessThanOrEqual": "140.*", "status": "unaffected", "version": "140.15", "versionType": "rpm"}, {"lessThanOrEqual": "153.*", "status": "unaffected", "version": "153.2", "versionType": "rpm"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "155", "versionType": "rpm"}]}], "source": "security@mozilla.org"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Sandbox escape due to use-after-free in the DOM: Security component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, and Firefox ESR 153.2."}], "id": "CVE-2026-84121", "lastModified": "2026-09-01T13:20:05.933", "metrics": {}, "published": "2026-09-01T13:20:05.933", "references": [{"source": "security@mozilla.org", "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2059018"}, {"source": "security@mozilla.org", "url": "https://www.mozilla.org/security/advisories/mfsa2026-82/"}, {"source": "security@mozilla.org", "url": "https://www.mozilla.org/security/advisories/mfsa2026-83/"}, {"source": "security@mozilla.org", "url": "https://www.mozilla.org/security/advisories/mfsa2026-84/"}, {"source": "security@mozilla.org", "url": "https://www.mozilla.org/security/advisories/mfsa2026-85/"}], "sourceIdentifier": "security@mozilla.org", "vulnStatus": "Received"}

{}

{"affected": [{"configurations": [{"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[115.40,115.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[140.15,140.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[153.2,153.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[155,*]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Firefox", "source": "cna", "vendor": "Mozilla"}, "product": "firefox", "vendor": "mozilla"}], "created": "2026-09-01T13:30:16.908305+00:00", "updated": "2026-09-01T13:30:16.908334+00:00", "vendors": ["mozilla", "mozilla$PRODUCT$firefox"]}