Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. Prior to 0.10.0, the /api/v1/auths/signin endpoint looked users up by email and only ran bcrypt password verification when a credential existed, making registered-account attempts measurably slower than missing-email attempts and allowing unauthenticated account enumeration. This issue is fixed in version 0.10.0.

Open WebUI: Account enumeration via observable login timing discrepancy