A Time-of-Check-Time-of-Use (TOCTOU) race condition exists in Craft CMS’s token validation service for tokens that explicitly set a limited usage. The getTokenRoute() method reads a token’s usage count, checks if it’s within limits, then updates the database in separate non-atomic operations. By sending concurrent requests, an attacker can use a single-use impersonation token multiple times before the database update completes.
To make this work, an attacker needs to obtain a valid user account impersonation URL with a non-expired token via some other means and exploit a race condition while bypassing any rate-limiting rules in place.
For this to be a privilege escalation, the impersonation URL must include a token for a user account with more permissions than the current user.
https://github.com/craftcms/cms/commit/3e4afe18279951c024c64896aa2b93cda6d95fdf
{
"cwe_ids": [
"CWE-367"
],
"github_reviewed": true,
"github_reviewed_at": "2026-02-23T22:16:22Z",
"nvd_published_at": "2026-02-24T03:16:02Z",
"severity": "MODERATE"
}