CVE-2026-62672 Grav: Authenticated ReDoS via regex_replace in Twig Sandbox
Authenticated editors can cause denial of service via catastrophic regex backtracking in Grav CMS when Twig content processing is enabled.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-62672?
CVE-2026-62672 is a medium-severity denial of service vulnerability in getgrav grav, published on 19 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Grav is a file-based Web platform. Prior to 2.0.4, Grav allowlists the regex_replace filter and function in system/config/security.yaml, and GravExtension::regexReplace() passes an editor-controlled pattern directly to preg_replace(). When security.twig_content.process_enabled is enabled, an authenticated page editor can publish a catastrophically backtracking pattern that consumes PHP worker CPU and denies service to site visitors. This issue is fixed in version 2.0.4.
Weakness: CWE-1333
Which versions are affected by CVE-2026-62672?
How do I fix CVE-2026-62672?
Upgrade to a fixed version.
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-2026-62672 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-62672 exists.