ZDI-26-133: Music Assistant Remote Code Execution Vulnerability (CVE-2026-26975) Demonstrated at Pwn2Own
A critical unauthenticated remote code execution vulnerability in Music Assistant, CVE-2026-26975, was disclosed by ZDI after being demonstrated at Pwn2Own, allowing network-adjacent attackers to execute arbitrary code as root.
A critical vulnerability in Music Assistant, a popular open-source music server, has been disclosed as part of the Zero Day Initiative's (ZDI) Pwn2Own contest. Tracked as ZDI-26-133 and CVE-2026-26975, the flaw allows network-adjacent attackers to execute arbitrary code without authentication, with a CVSS score of 8.8.
The vulnerability resides in the `_update_library_item` method, where the software fails to properly validate a user-supplied path before using it in file operations. This external control of a file path enables an attacker to write arbitrary files to the system, leading to remote code execution in the context of the root user. The exploit requires network adjacency, meaning the attacker must be on the same network as the target, but no user interaction is needed.
Music Assistant is a self-hosted music server that manages and streams personal music libraries. It is deployed on various platforms, including Linux, Docker, and potentially embedded devices. The vulnerability affects all versions prior to the fix, and given the software's widespread use among home users and enthusiasts, the potential impact is significant.
The vulnerability was discovered and reported by researchers Emanuele Barbeno, Cyrill Bannwart, Urs Mueller, Lukasz D, and Yves Bieri of Compass Security. They demonstrated the exploit at the Pwn2Own hacking contest, which awards prizes for zero-day vulnerabilities. The disclosure timeline shows the vulnerability was reported to the vendor on November 5, 2025, and a coordinated public release occurred on March 3, 2026.
Music Assistant has released a fix via a GitHub security advisory, available at https://github.com/music-assistant/server/security/advisories/GHSA-7jcc-p6xr-835j. Users are strongly advised to update their installations immediately to prevent potential exploitation. No in-the-wild exploitation has been reported at this time.
This disclosure highlights the ongoing importance of proper input validation in file operations, especially in software that handles user-supplied paths. The inclusion of this vulnerability in Pwn2Own underscores the value placed on finding and fixing such flaws before they can be weaponized by malicious actors.