CVE-2026-100803

{"id": "CVE-2026-100803", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-100803", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "version": "2.0.3", "timestamp": "2026-10-01T15:15:51.082535Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 8.1, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N", "integrityImpact": "HIGH", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.2, "exploitabilityScore": 2.8}]}, "affected": [{"source": "security@mozilla.org", "affectedData": [{"vendor": "Mozilla", "product": "Firefox", "versions": [{"status": "unaffected", "version": "115.42", "versionType": "rpm", "lessThanOrEqual": "115.*"}, {"status": "unaffected", "version": "140.17", "versionType": "rpm", "lessThanOrEqual": "140.*"}, {"status": "unaffected", "version": "153.4", "versionType": "rpm", "lessThanOrEqual": "153.*"}, {"status": "unaffected", "version": "157", "versionType": "rpm", "lessThanOrEqual": "*"}]}, {"vendor": "Mozilla", "product": "Thunderbird", "versions": [{"status": "unaffected", "version": "140.17", "versionType": "rpm", "lessThanOrEqual": "140.*"}, {"status": "unaffected", "version": "153.4", "versionType": "rpm", "lessThanOrEqual": "153.*"}, {"status": "unaffected", "version": "157", "versionType": "rpm", "lessThanOrEqual": "*"}]}]}], "published": "2026-09-29T13:17:45.390", "references": [{"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2057988", "tags": ["Permissions Required"], "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-100/", "tags": ["Vendor Advisory"], "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-101/", "tags": ["Vendor Advisory"], "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-102/", "tags": ["Vendor Advisory"], "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-103/", "tags": ["Vendor Advisory"], "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-97/", "tags": ["Vendor Advisory"], "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-98/", "tags": ["Vendor Advisory"], "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-99/", "tags": ["Vendor Advisory"], "source": "security@mozilla.org"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "description": [{"lang": "en", "value": "CWE-346"}]}], "descriptions": [{"lang": "en", "value": "Same-origin policy bypass in the WebExtensions component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17."}], "lastModified": "2026-10-19T17:47:25.023", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "9D4A8C0D-2E00-4182-A7A2-0F669C935655", "versionEndExcluding": "115.42.0"}, {"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "A5443D2F-B495-4F49-BD35-79AE67BA1E1C", "versionEndExcluding": "140.17.0", "versionStartIncluding": "116.0"}, {"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "59A9D6A8-7187-4134-8193-D0E325115773", "versionEndExcluding": "153.4.0", "versionStartIncluding": "141.0"}, {"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "CC64A654-10B5-4600-9E71-A2B276C5EAC3", "versionEndExcluding": "157.0.0", "versionStartIncluding": "154.0.0"}, {"criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "D25C5E0F-CC93-48A0-A656-29450505E8C6", "versionEndExcluding": "140.17.0"}, {"criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "90E6FA6F-4AD3-4A75-A02F-5B668644087B", "versionEndExcluding": "153.4.0", "versionStartIncluding": "141.0"}, {"criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "8A93E2FC-CEDC-4074-B587-70CD89C5BC2B", "versionEndExcluding": "157.0", "versionStartIncluding": "154.0"}], "operator": "OR"}]}], "sourceIdentifier": "security@mozilla.org"}