ZITADEL provides identity infrastructure. ZITADEL provides administrators the possibility to define a "Lockout Policy" with a maximum amount of failed password check attempts. On every failed password check, the amount of failed checks is compared against the configured maximum. Exceeding the limit, will lock the user and prevent further authentication. In the affected implementation it was possible for an attacker to start multiple parallel password checks, giving him the possibility to try out more combinations than configured in the "Lockout Policy". This vulnerability has been patched in versions 2.40.5 and 2.38.3.