Nexus Repository 3 - Server-Side Request Forgery (SSRF) via HTTP Redirect

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.