CVE-2026-46628: Twig: The `spaceless` filter implicitly marks its output as safe

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 2026-10-24
Weakness: CWE-116

Description

Twig is a template language for PHP. Prior to 3.26.0, the deprecated spaceless filter is registered as safe for HTML, causing Twig autoescaping to emit attacker-controlled markup unescaped when spaceless is applied to untrusted input. 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/3190b9ae12614dfd58cc5d8f394bac4708b17913
https://github.com/twigphp/Twig/releases/tag/v3.26.0
https://github.com/twigphp/Twig/security/advisories/GHSA-4j38-f5cw-54h7
https://github.com/twigphp/Twig/security/advisories/GHSA-4j38-f5cw-54h7

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