Vulnerabilidades de Miniflux

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 proxy_url. Attackers can point proxy_url at loopback or internal hosts, bypassing FETCHER_ALLOW_PRIVATE_NETWORKS checks to probe internal ports and send proxy-style requests to internal services.

Miniflux 2 is an open source feed reader. Prior to 2.3.1, IsRelativePath in internal/urllib/url.go accepts redirect targets containing backslashes because Go URL parsing treats them as path characters. Browser backslash normalization converts them to forward slashes. An unauthenticated attacker can provide such a redirect_url value to the login flow, bypass the relative-path and host checks, and redirect a victim to an attacker-controlled external site. This issue is fixed in version 2.3.1.

Miniflux 2 is an open source feed reader. Prior to version 2.2.16, Miniflux's media proxy endpoint (`GET /proxy/{encodedDigest}/{encodedURL}`) can be abused to perform Server-Side Request Forgery (SSRF). An authenticated user can cause Miniflux to generate a signed proxy URL for attacker-chosen media URLs embedded in feed entry content, including internal addresses (e.g., localhost, private RFC1918 ranges, or link-local metadata endpoints). Requesting the resulting `/proxy/...` URL makes Miniflux fetch and return the internal response. Version 2.2.16 fixes the issue.

Miniflux 2 is an open source feed reader. Versions 2.2.14 and below treat redirect_url as safe when url.Parse(...).IsAbs() is false, enabling phishing flows after login. Protocol-relative URLs like //ikotaslabs.com have an empty scheme and pass that check, allowing post-login redirects to attacker-controlled sites. This issue is fixed in version 2.2.15.