CVE-2025-55204: Muffon

Critical severity, CVSS 9.6. EPSS: 0.7% chance of exploitation in the next 30 days.

muffon is a cross-platform music streaming client for desktop. Versions prior to 2.3.0 have a one-click Remote Code Execution (RCE) vulnerability in. An attacker can exploit this issue by embedding a specially crafted `muffon://` link on any website they control. When a victim visits the site or clicks the link, the browser triggers Muffon’s custom URL handler, causing the application to launch and process the URL. This leads to RCE on the victim's machine without further interaction. Version 2.3.0 patches the issue.

Affected products

• Muffon Muffon: before 2.3.0 (fixed in 2.3.0)

Published 2026-01-05. Last modified 2026-10-07.