CVE-2026-44183: Cleanuparr

Critical severity, CVSS 9.8. EPSS: 0.3% chance of exploitation in the next 30 days.

Cleanuparr is a tool for automating the cleanup of unwanted or blocked files in Sonarr, Radarr, and supported download clients like qBittorrent. Prior to 2.9.10, TrustedNetworkAuthenticationHandler.ResolveClientIp parses the leftmost entry of the X-Forwarded-For header as the client IP. That entry is attacker-controlled — X-Forwarded-For is append-only, so the leftmost value is whatever the original HTTP client claimed. By sending a spoofed local IP in the header, an unauthenticated remote attacker passes the trusted-network check and is logged in as the Cleanuparr administrator. This vulnerability is fixed in 2.9.10.

Affected products

• Cleanuparr Cleanuparr: before 2.9.10 (fixed in 2.9.10)

Published 2026-05-12. Last modified 2026-06-17.