An open redirect vulnerability exists in the Directus SAML authentication callback endpoint. The RelayState parameter is used in redirects without proper validation against an allowlist of permitted domains.
During SAML authentication, the RelayState parameter is intended to preserve the user's original destination. However, while the login initiation flow validates redirect targets against allowed domains, this validation is not applied to the callback endpoint. This allows an attacker to craft a malicious authentication request that redirects users to an arbitrary external URL upon completion.
The vulnerability is present in both the success and error handling paths of the callback.
This vulnerability can be exploited without authentication.
{
"github_reviewed_at": "2026-01-06T19:22:38Z",
"github_reviewed": true,
"cwe_ids": [
"CWE-601"
],
"nvd_published_at": "2026-01-08T15:15:45Z",
"severity": "MODERATE"
}