{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-45127", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-05-08T20:08:17.208Z", "datePublished": "2026-08-18T15:38:41.434Z", "dateUpdated": "2026-08-18T15:38:41.434Z"}, "containers": {"cna": {"title": "MyBB: ACP Mass Mail draft resend CSRF", "problemTypes": [{"descriptions": [{"cweId": "CWE-352", "lang": "en", "description": "CWE-352: Cross-Site Request Forgery (CSRF)", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 3.5, "baseSeverity": "LOW", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N", "version": "3.1"}}], "references": [{"name": "https://github.com/mybb/mybb/security/advisories/GHSA-xx78-g79m-qvgq", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/mybb/mybb/security/advisories/GHSA-xx78-g79m-qvgq"}, {"name": "https://github.com/mybb/mybb/commit/a95c5d6730b943adab7e54bc209c051f98843a3b", "tags": ["x_refsource_MISC"], "url": "https://github.com/mybb/mybb/commit/a95c5d6730b943adab7e54bc209c051f98843a3b"}, {"name": "https://github.com/mybb/mybb/releases/tag/mybb_1840", "tags": ["x_refsource_MISC"], "url": "https://github.com/mybb/mybb/releases/tag/mybb_1840"}, {"name": "https://mybb.com/versions/1.8.40", "tags": ["x_refsource_MISC"], "url": "https://mybb.com/versions/1.8.40"}], "affected": [{"vendor": "mybb", "product": "mybb", "versions": [{"version": "< 1.8.40", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-08-18T15:38:41.434Z"}, "descriptions": [{"lang": "en", "value": "MyBB is free and open source forum software. Prior to 1.8.40, the ACP Mass Mail module does not validate certain requests correctly, allowing same-site attackers to create draft entries from archived entries by embedding a specially crafted URL. The Resend route in Admin CP, Users & Groups, Mass Mail, Mass Mailing Archive duplicates archived mailing entries into new drafts with mybb_massemails.status set to 0 on GET requests without request forgery protection. The uniquely identifying implementation details include Users & Groups \u2192 Mass Mail \u2192 Mass Mailing Archive, mybb_massemails.status = 0, and admin/modules/user/mass_mail.php. This issue is fixed in version 1.8.40."}], "source": {"advisory": "GHSA-xx78-g79m-qvgq", "discovery": "UNKNOWN"}}}}

{}

{"affected": [{"affectedData": [{"product": "mybb", "vendor": "mybb", "versions": [{"status": "affected", "version": "< 1.8.40"}]}], "source": "security-advisories@github.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "MyBB is free and open source forum software. Prior to 1.8.40, the ACP Mass Mail module does not validate certain requests correctly, allowing same-site attackers to create draft entries from archived entries by embedding a specially crafted URL. The Resend route in Admin CP, Users & Groups, Mass Mail, Mass Mailing Archive duplicates archived mailing entries into new drafts with mybb_massemails.status set to 0 on GET requests without request forgery protection. The uniquely identifying implementation details include Users & Groups \u2192 Mass Mail \u2192 Mass Mailing Archive, mybb_massemails.status = 0, and admin/modules/user/mass_mail.php. This issue is fixed in version 1.8.40."}], "id": "CVE-2026-45127", "lastModified": "2026-08-18T16:17:07.947", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 3.5, "baseSeverity": "LOW", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 2.1, "impactScore": 1.4, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-08-18T16:17:07.947", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/mybb/mybb/commit/a95c5d6730b943adab7e54bc209c051f98843a3b"}, {"source": "security-advisories@github.com", "url": "https://github.com/mybb/mybb/releases/tag/mybb_1840"}, {"source": "security-advisories@github.com", "url": "https://github.com/mybb/mybb/security/advisories/GHSA-xx78-g79m-qvgq"}, {"source": "security-advisories@github.com", "url": "https://mybb.com/versions/1.8.40"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-352"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,1.8.40)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "mybb", "source": "cna", "vendor": "mybb"}, "product": "mybb", "vendor": "mybb"}], "created": "2026-08-18T16:30:05.989771+00:00", "updated": "2026-08-18T17:30:15.394831+00:00", "vendors": ["mybb", "mybb$PRODUCT$mybb"]}