Packagist/symfony/symfony CVE-2026-45305: low, EPSS 0.68%

Symfony's YAML Parser has a ReDoS via Catastrophic Backtracking in Parser::cleanup() Regex

Action: Upgrade symfony/symfony to 5.4.52 or later.

composer require symfony/symfony:5.4.52

composer require symfony/symfony:6.4.40

composer require symfony/symfony:7.4.12

composer require symfony/symfony:8.0.12

Affected

Fixed versions

Sources

• osv: GHSA-9frc-8383-795m#Packagist/symfony/symfony
• https://github.com/symfony/symfony/security/advisories/GHSA-9frc-8383-795m
• https://github.com/symfony/symfony/commit/9749cd43c5e09b3735093623670b21b9d8a056cb
• https://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/symfony/CVE-2026-45305.yaml
• https://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/yaml/CVE-2026-45305.yaml
• https://github.com/symfony/symfony
• https://symfony.com/cve-2026-45305

CVE-2026-45305 · published 2026-05-27T21:34:35Z · modified 2026-09-10T03:51:05.233135111Z · JSON