Medium · published August 20, 2026
The scanFeedsResolver in packages/api/src/resolvers/subscriptions/index.ts passes the caller-supplied url straight to axios.get(url, rssParserConfig()) with no address validation. The same file guards the subscribe path with validateUrl(), which rejects private and reserved ranges through the private-ip library, and createPageSaveRequest applies the same check, so the omission is specific to this resolver. An authenticated user can direct the server to request arbitrary internal endpoints. The response is parsed as a feed or as HTML and the resolver returns the resulting url, title, description and type fields, so disclosure is limited to feed-shaped metadata and to link elements advertising RSS or Atom feeds; requests that do not parse still distinguish reachable ports from unreachable ones through the resulting error.