RCE in Muffon

CVE-2025-55204

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.

Vulnerability class: RCE (Remote Code Execution)

EPSS: 0.006 (45.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-55204?
CVE-2025-55204 is a high-severity vulnerability in Muffon, classified under Code Injection. CVSS score: 8.8/10. Published 2026-01-05.
How severe is CVE-2025-55204?
High severity. CVSS v3 base score is 8.8 out of 10.