CVE-2026-46637: Twig: HTML-output filters in twig/* extras incorrectly declared `is_safe => ['all']`

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-07-14 · updated 2026-07-16
Weakness: CWE-116

Description

Twig is a template language for PHP. Prior to 3.26.0, several filters in twig/markdown-extra and twig/cssinliner-extra are registered with is_safe => [all], causing Twig to treat plain text or HTML output as safe in HTML, JavaScript, CSS, URL, and other contexts where the output is not properly escaped. This issue is fixed in version 3.26.0.

Affected products

twigphp Twig: before 3.26.0 — fixed in 3.26.0

How to fix

Upgrade to a fixed version: twigphp Twig 3.26.0. Check the vendor advisory for mitigations.

References

https://github.com/twigphp/Twig/commit/84982072c79a7417b0d158a401d91344f3658299
https://github.com/twigphp/Twig/commit/e36489d3521ecbfc08bdcc61294302557035f14a
https://github.com/twigphp/Twig/releases/tag/v3.26.0
https://github.com/twigphp/Twig/security/advisories/GHSA-jv8m-2544-3pg3

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