{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-8956", "assignerOrgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "state": "PUBLISHED", "assignerShortName": "mozilla", "dateReserved": "2026-05-19T12:29:50.365Z", "datePublished": "2026-05-19T12:29:51.114Z", "dateUpdated": "2026-05-19T17:10:49.476Z"}, "containers": {"cna": {"affected": [{"product": "Firefox", "vendor": "Mozilla", "versions": [{"status": "unaffected", "version": "140.11", "lessThanOrEqual": "140.*", "versionType": "rpm"}, {"status": "unaffected", "version": "151", "lessThanOrEqual": "*", "versionType": "rpm"}]}, {"product": "Thunderbird", "vendor": "Mozilla", "versions": [{"status": "unaffected", "version": "140.11", "lessThanOrEqual": "140.*", "versionType": "rpm"}, {"status": "unaffected", "version": "151", "lessThanOrEqual": "*", "versionType": "rpm"}]}], "descriptions": [{"lang": "en", "value": "Integer overflow in the Networking: JAR component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.", "supportingMedia": [{"type": "text/html", "base64": false, "value": "Integer overflow in the Networking: JAR component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11."}]}], "title": "Integer overflow in the Networking: JAR component", "references": [{"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2032427"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-46/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-48/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-50/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-51/"}], "credits": [{"lang": "en", "value": "Yaqoub Aldurayhim"}], "providerMetadata": {"orgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "shortName": "mozilla", "dateUpdated": "2026-05-19T17:10:49.476Z"}}, "adp": [{"problemTypes": [{"descriptions": [{"type": "CWE", "cweId": "CWE-190", "lang": "en", "description": "CWE-190 Integer Overflow or Wraparound"}]}], "metrics": [{"cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 9.8, "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}}, {"other": {"type": "ssvc", "content": {"timestamp": "2026-05-19T16:37:45.418477Z", "id": "CVE-2026-8956", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"Technical Impact": "total"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-05-19T16:39:48.181Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 9.8, "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}}, {"other": {"type": "ssvc", "content": {"id": "CVE-2026-8956", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2026-05-19T16:37:45.418477Z"}}}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-190", "description": "CWE-190 Integer Overflow or Wraparound"}]}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-05-19T16:39:14.659Z"}}], "cna": {"title": "Integer overflow in the Networking: JAR component", "credits": [{"lang": "en", "value": "Yaqoub Aldurayhim"}], "affected": [{"vendor": "Mozilla", "product": "Firefox", "versions": [{"status": "unaffected", "version": "140.11", "versionType": "rpm", "lessThanOrEqual": "140.*"}, {"status": "unaffected", "version": "151", "versionType": "rpm", "lessThanOrEqual": "*"}]}, {"vendor": "Mozilla", "product": "Thunderbird", "versions": [{"status": "unaffected", "version": "140.11", "versionType": "rpm", "lessThanOrEqual": "140.*"}, {"status": "unaffected", "version": "151", "versionType": "rpm", "lessThanOrEqual": "*"}]}], "references": [{"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2032427"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-46/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-48/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-50/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-51/"}], "descriptions": [{"lang": "en", "value": "Integer overflow in the Networking: JAR component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.", "supportingMedia": [{"type": "text/html", "value": "Integer overflow in the Networking: JAR component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.", "base64": false}]}], "providerMetadata": {"orgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "shortName": "mozilla", "dateUpdated": "2026-05-19T17:10:49.476Z"}}}, "cveMetadata": {"cveId": "CVE-2026-8956", "state": "PUBLISHED", "dateUpdated": "2026-05-19T17:10:49.476Z", "dateReserved": "2026-05-19T12:29:50.365Z", "assignerOrgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "datePublished": "2026-05-19T12:29:51.114Z", "assignerShortName": "mozilla"}, "dataVersion": "5.2"}

{"configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*", "matchCriteriaId": "51216802-B743-4D96-9262-A4B0ECB71A0E", "versionEndExcluding": "140.11.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*", "matchCriteriaId": "7C197B6D-C48E-4D7E-A1C0-52E081E97DF0", "versionEndExcluding": "151.0.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*", "matchCriteriaId": "35057096-2597-4FB5-AACB-E68FBE0A11A1", "versionEndExcluding": "140.11", "vulnerable": true}, {"criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*", "matchCriteriaId": "84A85BEB-6467-4CDB-A533-FA3AA67B1CAE", "versionEndExcluding": "151.0.0", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Integer overflow in the Networking: JAR component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11."}], "id": "CVE-2026-8956", "lastModified": "2026-05-20T14:31:07.807", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 9.8, "baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 5.9, "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}, "published": "2026-05-19T14:16:51.943", "references": [{"source": "security@mozilla.org", "tags": ["Permissions Required"], "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2032427"}, {"source": "security@mozilla.org", "tags": ["Vendor Advisory"], "url": "https://www.mozilla.org/security/advisories/mfsa2026-46/"}, {"source": "security@mozilla.org", "tags": ["Vendor Advisory"], "url": "https://www.mozilla.org/security/advisories/mfsa2026-48/"}, {"source": "security@mozilla.org", "tags": ["Vendor Advisory"], "url": "https://www.mozilla.org/security/advisories/mfsa2026-50/"}, {"source": "security@mozilla.org", "tags": ["Vendor Advisory"], "url": "https://www.mozilla.org/security/advisories/mfsa2026-51/"}], "sourceIdentifier": "security@mozilla.org", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-190"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{"bugzilla": {"description": "firefox: Integer overflow in the Networking: JAR component", "id": "2479839", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2479839"}, "csaw": false, "cvss3": {"cvss3_base_score": "6.1", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N", "status": "draft"}, "cwe": "CWE-190", "details": ["A flaw was found in Firefox. The Mozilla Foundation's Security Advisory describes the following issue:\nInteger overflow in the Networking: JAR component"], "name": "CVE-2026-8956", "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": "2026-05-19T12:29:51Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-8956\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-8956\nhttps://www.mozilla.org/security/advisories/mfsa2026-48/#CVE-2026-8956"], "statement": "Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.", "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[140.11,140.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[151,*]"}}], "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": "2026-05-19T15:00:09.007853+00:00", "updated": "2026-05-19T21:30:14.353082+00:00", "vendors": ["mozilla", "mozilla$PRODUCT$firefox"]}