miniflux/v2 · Security
Miniflux Media Proxy vulnerable to Stored Cross-site Scripting due to improper Content-Security-Policy configuration
- GHSA ID
- GHSA-cq88-842x-2jhp
- CVE ID
- CVE-2025-31483
- Severity
- medium
- Published
- Updated
- CVSS v4
- 4.8 · CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N
Description
Summary
Due to a weak Content Security Policy on the /proxy/* route, an attacker can bypass the CSP of the media proxy and execute cross-site scripting when opening external images in a new tab/window.
Impact
A malicious feed added to Miniflux can execute arbitrary JavaScript in the user's browser when opening external resources, such as proxified images, in a new tab or window.
Mitigation
The CSP for the media proxy has been changed from default-src 'self' to default-src 'none'; form-action 'none'; sandbox;.
Upgrade to Miniflux >= 2.2.7
Credit
RyotaK (GMO Flatt Security Inc.) with takumi-san.ai
CWEs
- CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')