CVE-2026-45067
mediumpriority · track · 10EPSS 0.006 · 48 %ileexploit · PoCEUUSEPSS · scored 2026-10-27
### Description `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. The 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. ### Resolution The `Address` constructor now rejects addresses containing line breaks. The patch for this issue is available [here](https://github.com/symfony/symfony/commit/dc2dbd29211eb4ddc451373fa1374fb926e94604) for branch 5.4. ### Credits We would like to thank Claude Mythos Preview (via Project Glasswing) for reporting the issue and providing the fix.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 2.9–6.3
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
exploits (1)
Public proof-of-concept and weaponised exploit code.
- HORKimhab/CVE-2026-45067CVE-2026-45067 - DraftPoC · poc_in_github
affected products (12)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- GHSA-qpmx-3rfj-7rhvSymfony has Email Header / SMTP Command Injection via CRLF in Symfony\Component\Mime\Address2026-05-27ghsa · osvUS
### Description `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. The 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. ### Resolution The `Address` constructor now rejects addresses containing line breaks. The patch for this issue is available [here](https://github.com/symfony/symfony/commit/dc2dbd29211eb4ddc451373fa1374fb926e94604) for branch 5.4. ### Credits We would like to thank Claude Mythos Preview (via Project Glasswing) for reporting the issue and providing the fix.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (19)
External citations — patches, advisories, analysis.
- https://github.com/symfony/symfony/commit/a1c42cbe517bc146a54da7505a107ded317478fecnnvd
- https://github.com/symfony/symfony/releasesPatchcnnvd
- https://github.com/symfony/symfony/releases/tag/v5.4.52cnnvd
- https://github.com/symfony/symfony/releases/tag/v6.4.40cnnvd
- https://github.com/symfony/symfony/releases/tag/v7.4.12cnnvd
- https://github.com/symfony/symfony/releases/tag/v8.0.12cnnvd
- https://github.com/symfony/symfony/security/advisories/GHSA-qpmx-3rfj-7rhvcnnvd
- https://github.com/symfony/symfony/commit/a1c42cbe517bc146a54da7505a107ded317478feenisa_euvd
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