CVE-2025-55204 | muffon has One-click Remote Code Execution via XSS and Custom URL Handling

Exp

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.

Published: 2026-01-05 Last update: 2026-01-12 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2025-55204 is rated High Exploit Risk (68.8/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.30%). Core evidence: 2 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2025-55204

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2025-55204

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-03 0.50% 0.30% -0.20%
2 2026-05-07 0.36% 0.50% +0.15%
3 2026-03-14 0.36%

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-55204

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.8 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 5.9 [email protected]
9.6 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 6.0 [email protected]

Weakness enumeration for CVE-2025-55204

Affected software / configurations for CVE-2025-55204

Vendor Product Version Raw CPE
muffon muffon < 2.3.0 cpe:2.3:a:muffon:muffon:*:*:*:*:*:node.js:*:*

References for CVE-2025-55204

cvelogic Threat Intelligence