{"id":"CVE-2026-45067","aliases":["GHSA-qpmx-3rfj-7rhv"],"url":"https://o3.security/vulnerability/CVE-2026-45067","summary":"Symfony: Email Header / SMTP Command Injection via CRLF in Symfony\\Component\\Mime\\Address","details":"### Description\n\n`Symfony\\Component\\Mime\\Address` is the value-object every Symfony Mailer address (to/cc/bcc/from/reply-to) flows through; its constructor is documented as validating the address and throwing on invalid input, so developers treat it as a security boundary.\n\nThe constructor accepts email addresses whose local-part (the part before `@`) is an RFC-5322 *quoted string* containing raw `\\r\\n` bytes — e.g. `\"x\\r\\nBcc: attacker@evil\"@example.com`. The stored address is later emitted verbatim into (1) the rendered message headers and (2) `SmtpTransport`'s `MAIL FROM:<...>` / `RCPT TO:<...>` protocol lines, turning the embedded CRLF into a new mail header and/or a new SMTP command.\n\n### Resolution\n\nThe `Address` constructor now rejects addresses containing line breaks.\n\nThe patch for this issue is available [here](https://github.com/symfony/symfony/commit/dc2dbd29211eb4ddc451373fa1374fb926e94604) for branch 5.4.\n\n### Credits\n\nWe would like to thank Claude Mythos Preview (via Project Glasswing) for reporting the issue and providing the fix.","published":"2026-07-14T17:41:53.874Z","modified":"2026-08-12T03:51:23.946005367Z","cvss":null,"epss":{"score":0.00619,"percentile":0.46751,"asOf":"2026-08-16"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Packagist","name":"symfony/mime","fixedVersion":"5.4.52"},{"ecosystem":"Packagist","name":"symfony/symfony","fixedVersion":"5.4.52"},{"ecosystem":"Packagist","name":"symfony/mime","fixedVersion":"6.4.40"},{"ecosystem":"Packagist","name":"symfony/mime","fixedVersion":"7.4.12"},{"ecosystem":"Packagist","name":"symfony/mime","fixedVersion":"8.0.12"},{"ecosystem":"Packagist","name":"symfony/symfony","fixedVersion":"6.4.40"},{"ecosystem":"Packagist","name":"symfony/symfony","fixedVersion":"7.4.12"},{"ecosystem":"Packagist","name":"symfony/symfony","fixedVersion":"8.0.12"}],"fix":{"url":"https://github.com/symfony/symfony/commit/a1c42cbe517bc146a54da7505a107ded317478fe","label":"symfony/symfony@a1c42cb"},"references":[{"type":"WEB","url":"https://github.com/symfony/symfony/releases/tag/v5.4.52"},{"type":"WEB","url":"https://github.com/symfony/symfony/releases/tag/v6.4.40"},{"type":"WEB","url":"https://github.com/symfony/symfony/releases/tag/v7.4.12"},{"type":"WEB","url":"https://github.com/symfony/symfony/releases/tag/v8.0.12"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/45xxx/CVE-2026-45067.json"},{"type":"ADVISORY","url":"https://github.com/symfony/symfony/security/advisories/GHSA-qpmx-3rfj-7rhv"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-45067"},{"type":"FIX","url":"https://github.com/symfony/symfony/commit/a1c42cbe517bc146a54da7505a107ded317478fe"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:23.946005367Z"}}