Plane: OAuth Avatar Redirect SSRF Leads to Internal Data Exfiltration via Static Asset Endpoint

Plane is an open-source project management tool. Prior to 1.4.0, Plane's OAuth avatar synchronization flow fetches avatar_url from provider user data through a server-side HTTP request without internal IP validation and follows redirects by default. An attacker can provide an avatar URL that redirects to an internal-only resource, such as a metadata endpoint, and Plane uploads the fetched response as a user avatar file. The object is then exposed through /api/assets/v2/static/{asset_id}/, allowing exfiltration of internally fetched content. This issue is fixed in 1.4.0.