{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-8958", "assignerOrgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "state": "PUBLISHED", "assignerShortName": "mozilla", "dateReserved": "2026-05-19T12:29:53.304Z", "datePublished": "2026-05-19T12:29:54.014Z", "dateUpdated": "2026-05-19T17:10:50.174Z"}, "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": "Information disclosure, sandbox escape in the Security: Process Sandboxing 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": "Information disclosure, sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11."}]}], "title": "Information disclosure, sandbox escape in the Security: Process Sandboxing component", "references": [{"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2034713"}, {"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": "2026-05-19T17:10:50.174Z"}}, "adp": [{"problemTypes": [{"descriptions": [{"type": "CWE", "cweId": "CWE-668", "lang": "en", "description": "CWE-668 Exposure of Resource to Wrong Sphere"}]}, {"descriptions": [{"type": "CWE", "cweId": "CWE-693", "lang": "en", "description": "CWE-693 Protection Mechanism Failure"}]}], "metrics": [{"cvssV3_1": {"scope": "CHANGED", "version": "3.1", "baseScore": 8.6, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}}, {"other": {"type": "ssvc", "content": {"timestamp": "2026-05-19T15:03:48.961447Z", "id": "CVE-2026-8958", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"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": "2026-05-19T15:05:35.766Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"cvssV3_1": {"scope": "CHANGED", "version": "3.1", "baseScore": 8.6, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}}, {"other": {"type": "ssvc", "content": {"id": "CVE-2026-8958", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-05-19T15:03:48.961447Z"}}}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-668", "description": "CWE-668 Exposure of Resource to Wrong Sphere"}]}, {"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-693", "description": "CWE-693 Protection Mechanism Failure"}]}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-05-19T15:04:50.040Z"}}], "cna": {"title": "Information disclosure, sandbox escape in the Security: Process Sandboxing 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=2034713"}, {"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": "Information disclosure, sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.", "supportingMedia": [{"type": "text/html", "value": "Information disclosure, sandbox escape in the Security: Process Sandboxing 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": "2026-05-19T17:10:50.174Z"}}}, "cveMetadata": {"cveId": "CVE-2026-8958", "state": "PUBLISHED", "dateUpdated": "2026-05-19T17:10:50.174Z", "dateReserved": "2026-05-19T12:29:53.304Z", "assignerOrgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "datePublished": "2026-05-19T12:29:54.014Z", "assignerShortName": "mozilla"}, "dataVersion": "5.2"}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "Information disclosure, sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11."}], "id": "CVE-2026-8958", "lastModified": "2026-05-19T18:16:34.710", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 8.6, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "CHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 4.0, "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}, "published": "2026-05-19T14:16:52.170", "references": [{"source": "security@mozilla.org", "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2034713"}, {"source": "security@mozilla.org", "url": "https://www.mozilla.org/security/advisories/mfsa2026-46/"}, {"source": "security@mozilla.org", "url": "https://www.mozilla.org/security/advisories/mfsa2026-48/"}, {"source": "security@mozilla.org", "url": "https://www.mozilla.org/security/advisories/mfsa2026-50/"}, {"source": "security@mozilla.org", "url": "https://www.mozilla.org/security/advisories/mfsa2026-51/"}], "sourceIdentifier": "security@mozilla.org", "vulnStatus": "Undergoing Analysis", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-668"}, {"lang": "en", "value": "CWE-693"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{}

{"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": "2026-05-19T15:00:09.007496+00:00", "updated": "2026-05-19T20:30:13.403565+00:00", "vendors": ["mozilla", "mozilla$PRODUCT$firefox"]}