Allocation of Resources Without Limits or Throttling in Twig - CVE-2026-46629

 

Allocation of Resources Without Limits or Throttling in Twig - CVE-2026-46629

Published: May 20, 2026


Vulnerability identifier: #VU131994
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-46629
CWE-ID: CWE-770
Exploitation vector: Remote access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to allocation of resources without limits or throttling in IntlExtension formatter memoization when processing template-controlled formatter arguments. A remote attacker can supply many distinct locale, pattern, or formatting argument values to cause a denial of service.

On long-running runtimes where the Twig environment persists across requests, the cache can accumulate across requests, and the allocated ICU backing buffers are not bounded by PHP memory_limit.


Affected software

Twig
Debian Linux
php-twig (Debian package)

How to mitigate CVE-2026-46629

Install security update from vendor's website.

Twig - update to 3.26.0
php-twig (Debian package) - update to 3.5.1-1+deb12u3

External References

Related Security Bulletins