CVE-2026-45077

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, the server:log listener (Symfony\Bridge\Monolog\Command\ServerLogCommand) binds to 0.0.0.0:9911 by default and processes each received frame with unserialize(base64_decode($message)) without authentication, integrity checks, or an allowed_classes allowlist, allowing any reachable host to submit attacker-chosen serialized PHP payloads that can crash the listener and may trigger object-injection gadget effects. This issue is fixed in versions 5.4.52, 6.4.40, 7.4.12, and 8.0.12.

• github.comhttps://github.com/symfony/symfony/commit/0891b2f293896c488e26943dc034334364b77fc4
• github.comhttps://github.com/symfony/symfony/releases/tag/v5.4.52
• github.comhttps://github.com/symfony/symfony/releases/tag/v6.4.40
• github.comhttps://github.com/symfony/symfony/releases/tag/v7.4.12
• github.comhttps://github.com/symfony/symfony/releases/tag/v8.0.12
• github.comhttps://github.com/symfony/symfony/security/advisories/GHSA-m7v2-7gxm-vc2v