Nexus Repository 3 did not apply its existing Server-Side Request Forgery (SSRF) protections to HTTP redirect targets returned by proxy repository upstream servers. Any user with read access to a proxy repository backed by an attacker-controlled or compromised upstream server — including an anonymous user, if anonymous access is enabled — could receive a response from an internal network address or cloud metadata endpoint as repository content, potentially exposing sensitive information such as cloud IAM credentials.
Weakness
The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.