Intel

AIKIDO-2026-455080

symfony/twig-bridge is vulnerable to Deserialization of Untrusted Data

Deserialization of Untrusted Data Pre-CVE
Found by Aikido Intel before public disclosure or CVE publication.
Published Jul 1, 2026

59

Medium Risk

This Affects:

PHPsymfony/twig-bridge
6.0.0 - 6.4.40
Fixed in 6.4.42
7.0.0 - 7.4.12
Fixed in 7.4.14
8.0.0 - 8.0.12
Fixed in 8.0.14
8.1.0 - 8.1.0
Fixed in 8.1.1
Are you affected? Scan for Free

TL;DR

The TemplatedEmail and NotificationEmail classes restore typed string properties (such as htmlTemplate, textTemplate, locale, and theme) directly from the raw array passed to __unserialize(). When an attacker-controlled serialized payload places a \Stringable object into one of those string slots, PHP coerces it through __toString() before any validation runs, firing the gadget during unserialization. An application that deserializes untrusted data into these classes can therefore trigger attacker-chosen __toString() logic. The fix rejects \Stringable values in the raw data before any typed-string assignment and throws an exception.

Who does this affect?

You are affected if you are using a version that falls within the vulnerable range and your application deserializes untrusted data into the TemplatedEmail or NotificationEmail classes.

Background info

symfony/twig-bridge is vulnerable to Deserialization of Untrusted Data in versions 6.0.0 - 6.4.40, 7.0.0 - 7.4.12, 8.0.0 - 8.0.12 and 8.1.0 - 8.1.0.

How to fix this

Upgrade the symfony/twig-bridge and/or the symfony/symfony library to the patch version.