{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-45125", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-05-08T20:08:17.208Z", "datePublished": "2026-08-18T15:50:38.936Z", "dateUpdated": "2026-08-18T17:46:25.763Z"}, "containers": {"cna": {"title": "MyBB: Email User CRLF injection", "problemTypes": [{"descriptions": [{"cweId": "CWE-93", "lang": "en", "description": "CWE-93: Improper Neutralization of CRLF Sequences ('CRLF Injection')", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N", "version": "3.1"}}], "references": [{"name": "https://github.com/mybb/mybb/security/advisories/GHSA-f626-53q9-pqm9", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/mybb/mybb/security/advisories/GHSA-f626-53q9-pqm9"}, {"name": "https://github.com/mybb/mybb/commit/5046c56b515d4593297a4f65b0c6ccb0b55baa01", "tags": ["x_refsource_MISC"], "url": "https://github.com/mybb/mybb/commit/5046c56b515d4593297a4f65b0c6ccb0b55baa01"}, {"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": "2026-08-18T15:50:38.936Z"}, "descriptions": [{"lang": "en", "value": "MyBB is free and open source forum software. Prior to 1.8.40, the Email User controller does not sanitize sender names correctly, resulting in mail header injection. member.php?action=do_emailuser accepts the fromname HTTP parameter for guests or the stored username for authenticated users when the cansendemail group permission is enabled. When mail_handler is set to the default PHP mail value, the sender name is used without sanitization in Return-Path and Reply-To headers, allowing arbitrary headers to be injected with CRLF sequences. This issue is fixed in version 1.8.40."}], "source": {"advisory": "GHSA-f626-53q9-pqm9", "discovery": "UNKNOWN"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-08-18T17:44:38.156362Z", "id": "CVE-2026-45125", "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": "2026-08-18T17:46:25.763Z"}}]}}

{}

{"affected": [{"affectedData": [{"product": "mybb", "vendor": "mybb", "versions": [{"status": "affected", "version": "< 1.8.40"}]}], "source": "[email protected]"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "MyBB is free and open source forum software. Prior to 1.8.40, the Email User controller does not sanitize sender names correctly, resulting in mail header injection. member.php?action=do_emailuser accepts the fromname HTTP parameter for guests or the stored username for authenticated users when the cansendemail group permission is enabled. When mail_handler is set to the default PHP mail value, the sender name is used without sanitization in Return-Path and Reply-To headers, allowing arbitrary headers to be injected with CRLF sequences. This issue is fixed in version 1.8.40."}], "id": "CVE-2026-45125", "lastModified": "2026-08-18T16:17:07.667", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 1.4, "source": "[email protected]", "type": "Secondary"}]}, "published": "2026-08-18T16:17:07.667", "references": [{"source": "[email protected]", "url": "https://github.com/mybb/mybb/commit/5046c56b515d4593297a4f65b0c6ccb0b55baa01"}, {"source": "[email protected]", "url": "https://github.com/mybb/mybb/releases/tag/mybb_1840"}, {"source": "[email protected]", "url": "https://github.com/mybb/mybb/security/advisories/GHSA-f626-53q9-pqm9"}, {"source": "[email protected]", "url": "https://mybb.com/versions/1.8.40"}], "sourceIdentifier": "[email protected]", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-93"}], "source": "[email protected]", "type": "Primary"}]}

{}

{}