VulnerabilityDeferred

CVE-2026-44183

That entry is attacker-controlled — X-Forwarded-For is append-only, so the leftmost value is whatever the original HTTP client claimed.

CRITICAL 9.8EPSS 0.22%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.22%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

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.

CVSS 3.1: 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS: 0.22% probability · 13th percentile
CISA KEV: Not listed
Weakness: CWE-290, CWE-348
Source: security-advisories@github.com

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.