CVE-2026-45070

Medium

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.

SeverityMedium
CVSS6.5
Exploit probability—
ProductSensiolabs Symfony
PublishedJul 14, 2026
First seenJul 14, 2026
Weakness typeCWE-93CWE-93

How to fix

Update
  • sensiolabs symfony5.4.52, 6.4.40, 7.4.12, 8.0.12 or later
  • symfony/mime5.4.52, 6.4.40, 7.4.12, 8.0.12 or later
  • symfony/symfony5.4.52, 6.4.40, 7.4.12, 8.0.12 or later

Affected products

ProductAffected versionsFixed in
sensiolabs symfonyv < 5.4.52, 6.0.0 ≤ v < 6.4.40, 7.0.0 ≤ v < 7.4.12, 8.0.0 ≤ v < 8.0.125.4.52, 6.4.40, 7.4.12, 8.0.12
symfony/mimePackagistv < 5.4.52, 6.0.0 ≤ v < 6.4.40, 7.0.0 ≤ v < 7.4.12, 8.0.0 ≤ v < 8.0.125.4.52, 6.4.40, 7.4.12, 8.0.12
symfony/symfonyPackagistv < 5.4.52, 6.0.0 ≤ v < 6.4.40, 7.0.0 ≤ v < 7.4.12, 8.0.0 ≤ v < 8.0.125.4.52, 6.4.40, 7.4.12, 8.0.12

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