CVE-2026-84120

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-84120", "assignerOrgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "state": "PUBLISHED", "assignerShortName": "mozilla", "dateReserved": "2026-09-01T07:25:08.573Z", "datePublished": "2026-09-01T12:18:40.455Z", "dateUpdated": "2026-09-01T21:44:08.380Z"}, "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"}]}, {"product": "Thunderbird", "vendor": "Mozilla", "versions": [{"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": "Use-after-free in the Audio/Video component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.", "supportingMedia": [{"type": "text/html", "base64": false, "value": "Use-after-free in the Audio/Video component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2."}]}], "title": "Use-after-free in the Audio/Video component", "references": [{"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2058911"}, {"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/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-86/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-87/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-88/"}], "credits": [{"lang": "en", "value": "Ukyo Akai"}], "providerMetadata": {"orgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "shortName": "mozilla", "dateUpdated": "2026-09-01T21:44:08.380Z"}}, "adp": [{"problemTypes": [{"descriptions": [{"type": "CWE", "cweId": "CWE-416", "lang": "en", "description": "CWE-416 Use After Free"}]}], "metrics": [{"cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.4, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N", "integrityImpact": "LOW", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "LOW"}}, {"other": {"type": "ssvc", "content": {"timestamp": "2026-09-01T13:47:00.121971Z", "id": "CVE-2026-84120", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-09-01T13:47:04.126Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.4, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N", "integrityImpact": "LOW", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "LOW"}}, {"other": {"type": "ssvc", "content": {"id": "CVE-2026-84120", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-09-01T13:47:00.121971Z"}}}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-416", "description": "CWE-416 Use After Free"}]}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-09-01T13:46:49.943Z"}}], "cna": {"title": "Use-after-free in the Audio/Video component", "credits": [{"lang": "en", "value": "Ukyo Akai"}], "affected": [{"vendor": "Mozilla", "product": "Firefox", "versions": [{"status": "unaffected", "version": "115.40", "versionType": "rpm", "lessThanOrEqual": "115.*"}, {"status": "unaffected", "version": "140.15", "versionType": "rpm", "lessThanOrEqual": "140.*"}, {"status": "unaffected", "version": "153.2", "versionType": "rpm", "lessThanOrEqual": "153.*"}, {"status": "unaffected", "version": "155", "versionType": "rpm", "lessThanOrEqual": "*"}]}, {"vendor": "Mozilla", "product": "Thunderbird", "versions": [{"status": "unaffected", "version": "140.15", "versionType": "rpm", "lessThanOrEqual": "140.*"}, {"status": "unaffected", "version": "153.2", "versionType": "rpm", "lessThanOrEqual": "153.*"}, {"status": "unaffected", "version": "155", "versionType": "rpm", "lessThanOrEqual": "*"}]}], "references": [{"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2058911"}, {"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/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-86/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-87/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-88/"}], "descriptions": [{"lang": "en", "value": "Use-after-free in the Audio/Video component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.", "supportingMedia": [{"type": "text/html", "value": "Use-after-free in the Audio/Video component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.", "base64": false}]}], "providerMetadata": {"orgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "shortName": "mozilla", "dateUpdated": "2026-09-01T21:44:08.380Z"}}}, "cveMetadata": {"cveId": "CVE-2026-84120", "state": "PUBLISHED", "dateUpdated": "2026-09-01T21:44:08.380Z", "dateReserved": "2026-09-01T07:25:08.573Z", "assignerOrgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "datePublished": "2026-09-01T12:18:40.455Z", "assignerShortName": "mozilla"}, "dataVersion": "5.2"}

{"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"}]}, {"product": "Thunderbird", "vendor": "Mozilla", "versions": [{"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"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*", "matchCriteriaId": "B84FE134-AC5B-4FF4-9F3C-704D92475BD1", "versionEndExcluding": "115.40.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*", "matchCriteriaId": "933C120C-6E83-48E4-8002-38E2C93D8E47", "versionEndExcluding": "140.15.0", "versionStartIncluding": "116.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*", "matchCriteriaId": "BAC56AB7-FB63-4A76-BFBD-4C0122F2A93C", "versionEndExcluding": "153.2.0", "versionStartIncluding": "141.0.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*", "matchCriteriaId": "56769A1A-4A97-4814-8963-24B7AFD7E44F", "versionEndExcluding": "155.0.0", "versionStartIncluding": "154.0.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*", "matchCriteriaId": "EC44CB46-89FD-40DC-92D1-F865A0521D06", "versionEndExcluding": "140.15.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*", "matchCriteriaId": "B217A29A-45B5-407C-9B4B-96CF6EB0838E", "versionEndExcluding": "153.2.0", "versionStartIncluding": "141.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*", "matchCriteriaId": "C6AB910B-074A-42F7-A3C7-B7E822011D92", "versionEndExcluding": "155.0", "versionStartIncluding": "154.0", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Use-after-free in the Audio/Video component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2."}], "id": "CVE-2026-84120", "lastModified": "2026-09-02T16:41:18.357", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.4, "baseSeverity": "MEDIUM", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 2.5, "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-84120", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-09-01T13:47:00.121971Z", "version": "2.0.3"}}]}, "published": "2026-09-01T13:20:05.817", "references": [{"source": "security@mozilla.org", "tags": ["Permissions Required"], "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2058911"}, {"source": "security@mozilla.org", "tags": ["Vendor Advisory"], "url": "https://www.mozilla.org/security/advisories/mfsa2026-82/"}, {"source": "security@mozilla.org", "tags": ["Vendor Advisory"], "url": "https://www.mozilla.org/security/advisories/mfsa2026-83/"}, {"source": "security@mozilla.org", "tags": ["Vendor Advisory"], "url": "https://www.mozilla.org/security/advisories/mfsa2026-84/"}, {"source": "security@mozilla.org", "tags": ["Vendor Advisory"], "url": "https://www.mozilla.org/security/advisories/mfsa2026-85/"}, {"source": "security@mozilla.org", "tags": ["Vendor Advisory"], "url": "https://www.mozilla.org/security/advisories/mfsa2026-86/"}, {"source": "security@mozilla.org", "tags": ["Vendor Advisory"], "url": "https://www.mozilla.org/security/advisories/mfsa2026-87/"}, {"source": "security@mozilla.org", "tags": ["Vendor Advisory"], "url": "https://www.mozilla.org/security/advisories/mfsa2026-88/"}], "sourceIdentifier": "security@mozilla.org", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-416"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{"bugzilla": {"description": "firefox: firefox-esr: Firefox: Arbitrary code execution via use-after-free in Audio/Video component", "id": "2526765", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2526765"}, "csaw": false, "cvss3": {"cvss3_base_score": "8.8", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-825", "details": ["A flaw was found in the Audio/Video component of Firefox and Firefox ESR. This use-after-free vulnerability could allow a remote attacker to achieve arbitrary code execution. A use-after-free occurs when a program attempts to use memory that has been deallocated, which can lead to memory corruption and unexpected program behavior. This could enable an attacker to take control of the affected system."], "name": "CVE-2026-84120", "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": "2026-09-01T12:18:40Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-84120\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-84120\nhttps://bugzilla.mozilla.org/show_bug.cgi?id=2058911\nhttps://www.mozilla.org/security/advisories/mfsa2026-82/\nhttps://www.mozilla.org/security/advisories/mfsa2026-83/\nhttps://www.mozilla.org/security/advisories/mfsa2026-84/\nhttps://www.mozilla.org/security/advisories/mfsa2026-85/"], "threat_severity": "Important"}

{"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": "2026-09-01T13:30:17.384674+00:00", "updated": "2026-09-02T04:30:04.702772+00:00", "vendors": ["mozilla", "mozilla$PRODUCT$firefox"]}