Description
Seerr is an open-source media request and discovery manager for Jellyfin, Plex, and Emby. Starting in version 2.0.0 and prior to version 3.1.0, an authentication guard logic flaw in `POST /api/v1/auth/jellyfin` allows an unauthenticated attacker to register a new Seerr account on any Plex-configured instance by authenticating with an attacker-controlled Jellyfin server. The attacker receives an authenticated session and can immediately use the application with default permissions, including the ability to submit media requests to Radarr/Sonarr. Any Seerr deployment where all three of the following are true may be vulnerable: `settings.main.mediaServerType` is set to `PLEX` (the most common deployment).; `settings.jellyfin.ip` is set to `""` (default, meaning Jellyfin was never configured); and `settings.main.newPlexLogin` is set to `true` (default). Jellyfin-configured and Emby-configured deployments are not affected. Version 3.1.0 of Seerr fixes this issue.
Problem types
CWE-288: Authentication Bypass Using an Alternate Path or Channel
CWE-807: Reliance on Untrusted Inputs in a Security Decision
Product status
References
github.com/.../seerr/security/advisories/GHSA-rc4w-7m3r-c2f7
github.com/...ommit/4ae20684092b5b28527b23dfbc1a3417858fee8e
github.com/seerr-team/seerr/releases/tag/v3.1.0