ZITADEL is an open-source identity infrastructure tool. Versions 4.0.0-rc.1 through 4.7.0 are vulnerable to DOM-Based XSS through the Zitadel V2 logout endpoint. The /logout endpoint insecurely routes to a value that is supplied in the post_logout_redirect GET parameter.

As a result, unauthenticated remote attacker can execute malicious JS code on Zitadel users’ browsers. To carry out an attack, multiple user sessions need to be active in the same browser, however, account takeover is mitigated when using Multi-Factor Authentication (MFA) or Passwordless authentication. This issue is fixed in version 4.7.1.