CVE-2026-46629 Twig: Unbounded formatter memoisation in twig/intl-extra keyed on template-controlled arguments

What is CVE-2026-46629?

CVE-2026-46629 is a medium-severity denial of service vulnerability in twigphp Twig, published on 14 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

Twig is a template language for PHP. Prior to 3.26.0, twig/intl-extra memoises IntlDateFormatter and NumberFormatter instances in arrays keyed by template-controlled filter arguments such as locale, pattern, and attrs, allowing a template to allocate many ICU formatter objects that remain pinned for the lifetime of the Twig\Environment. This issue is fixed in version 3.26.0.

Weakness: CWE-770

Which versions are affected by CVE-2026-46629?

2 open source packages ship an affected version, including twig/intl-extra. It affects 1 product.

Products include Symfony Twig.

How do I fix CVE-2026-46629?

Upgrade twig/intl-extra to 3.26.0 or later.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2026-46629 being exploited?

There is no known exploitation of CVE-2026-46629 in the wild and no public exploit code.

Other vulnerabilities in twigphp Twig

• CVE-2018-13818 Code injection in n/a Critical 9.8
• CVE-2026-46633 Twig: PHP code injection via `{% use %}` template name High 8.7
• CVE-2026-46640 Twig: Arbitrary PHP code execution via `_self.(<string>)` macro-reference compilation High 8.7
• CVE-2026-24425 Twig 2.16.x & 3.9.0-3.25.x Sandbox Bypass via SourcePolicyInterface High 8.7
• CVE-2024-45411 Twig has a possible sandbox bypass High 8.6

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2026-46629, GHSA-35wc-cvqg-78fp, UBUNTU-CVE-2026-46629.