Vulnerability · Published Jul 14, 2026 · Assigned by GitHub_M
CVE-2026-45070Symfony: Email Header Injection via Non-Token Characters in Mime Parameter Names
Medium 6.3
In plain English
A medium-severity security flaw in mime from symfony. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 33% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Symfony is a PHP framework for web and console applications and a set of reusable PHP components. Prior to 5.4.52, 6.4.40, 7.4.12, and 8.0.12, Symfony\Component\Mime\Header\ParameterizedHeader validates and encodes parameter values but emits parameter names verbatim, allowing a caller that derives a parameter name from untrusted input to include CRLF or other non-token bytes and inject additional headers into rendered structured mail headers such as Content-Type or Content-Disposition. This issue is reported as fixed in versions 5.4.52, 6.4.40, 7.4.12, and 8.0.12.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | symfony | no fix listed | DEBIAN-CVE-2026-45070 |
| Debian:13 | symfony | 6.4.49+dfsg-0+deb13u1 | DEBIAN-CVE-2026-45070 |
| Debian:14 | symfony | 7.4.22+dfsg-1 | DEBIAN-CVE-2026-45070 |
| Packagist | symfony/mime | 5.4.52 | GHSA-vqc8-7275-q272 |
| Packagist | symfony/mime | 8.0.12 | GHSA-vqc8-7275-q272 |
| Packagist | symfony/mime | 6.4.40 | GHSA-vqc8-7275-q272 |
| Packagist | symfony/mime | 7.4.12 | GHSA-vqc8-7275-q272 |
| Packagist | symfony/symfony | 8.0.12 | GHSA-vqc8-7275-q272 |
| Packagist | symfony/symfony | 5.4.52 | GHSA-vqc8-7275-q272 |
| Packagist | symfony/symfony | 6.4.40 | GHSA-vqc8-7275-q272 |
| Packagist | symfony/symfony | 7.4.12 | GHSA-vqc8-7275-q272 |
| Ubuntu:25.10 | symfony | no fix listed | UBUNTU-CVE-2026-45070 |
| Ubuntu:26.04:LTS | symfony | no fix listed | UBUNTU-CVE-2026-45070 |
| Ubuntu:26.10 | symfony | no fix listed | UBUNTU-CVE-2026-45070 |
Affected products (as reported)
Weakness: CWE-93 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
References
- https://github.com/symfony/symfony/security/advisories/GHSA-vqc8-7275-q272 x_refsource_CONFIRM
- https://github.com/symfony/symfony/commit/e62ea217f8b4ca8ae922ad0f949e0c4dc1f9b613 x_refsource_MISC
- https://github.com/symfony/symfony/releases/tag/v5.4.52 x_refsource_MISC
- https://github.com/symfony/symfony/releases/tag/v6.4.40 x_refsource_MISC
- https://github.com/symfony/symfony/releases/tag/v7.4.12 x_refsource_MISC
- https://github.com/symfony/symfony/releases/tag/v8.0.12 x_refsource_MISC