FileRise is a self-hosted web-based file manager with multi-file upload, editing, and batch operations. Prior to 3.23.0, FileRise maps an authenticated OIDC identity to a local account using mutable preferred_username or email claims and does not require email_verified for email-based naming. An attacker who can obtain provider-issued claims colliding with an existing local username can be logged in as that account, including the built-in administrator, even when automatic provisioning is disabled. Exploitability depends on the configured identity provider allowing the colliding claim. This issue is fixed in version 3.23.0.
When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.