Miniflux before 2.3.5 contains an insufficient session expiration vulnerability that allows attackers to retain account access because password changes do not revoke existing web sessions. Attackers holding a leaked password or copied session cookie keep access for up to 30 days, reading integration credentials, creating API keys, or registering passkeys.

Miniflux before 2.3.5 contains an unverified password change vulnerability that allows holders of a signed-in session to change the account password without supplying the current password. Attackers with a stolen session cookie or unattended device can submit new password fields via updateSettings to lock out the owner and take over the account.

Miniflux 2.3.0 through 2.3.3 contains a server-side request forgery vulnerability that allows authenticated users to reach internal addresses by setting a feed's proxyurl. Attackers can point proxyurl at loopback or internal hosts, bypassing FETCHERALLOWPRIVATENETWORKS checks to probe internal ports and send proxy-style requests to internal services.

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