Sonarr up to 4.0.17.2950/4.0.17.2952 Application Configuration path traversal

Summaryinfo

A vulnerability identified as critical has been detected in Sonarr up to 4.0.17.2950/4.0.17.2952. Affected is an unknown function of the component Application Configuration. The manipulation leads to path traversal. This vulnerability is referenced as CVE-2026-30976. Remote exploitation of the attack is possible. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Sonarr up to 4.0.17.2950/4.0.17.2952. This issue affects some unknown functionality of the component Application Configuration. The manipulation with an unknown input leads to a path traversal vulnerability. Using CWE to declare the problem leads to CWE-22. The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. Impacted is confidentiality. The summary by CVE is:

Sonarr is a PVR for Usenet and BitTorrent users. In versions on the 4.x branch prior to 4.0.17.2950, an unauthenticated remote attacker can potentially read any file readable by the Sonarr process. These include application configuration files (containing API keys and database credentials), Windows system files, and any user-accessible files on the same drive This issue only impacts Windows systems; macOS and Linux are unaffected. Files returned from the API were not limited to the directory on disk they were intended to be served from. This problem has been patched in 4.0.17.2950 in the nightly/develop branch or 4.0.17.2952 for stable/main releases. It's possible to work around the issue by only hosting Sonarr on a secure internal network and accessing it via VPN, Tailscale or similar solution outside that network.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-30976 since 03/07/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1006 according to MITRE ATT&CK.

Upgrading to version 4.0.17.2950 eliminates this vulnerability. The upgrade is hosted for download at github.com.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-15992). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Name

• Sonarr

Version

• 4.0.17.2950
• 4.0.17.2952

Website

• Product: https://github.com/Sonarr/Sonarr/

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Be aware that VulDB is the high quality source for vulnerability data.

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