CVE-2026-91143 [HIGH] – goproxy through 15.3 fails to apply HTTP proxy basic authentication to CONNECT tunnel requ

goproxy through 15.3 fails to apply HTTP proxy basic authentication to CONNECT tunnel requests, allowing unauthenticated clients to bypass credential requirements. Attackers can issue CONNECT requests to establish tunnels through the authenticated proxy without providing credentials, enabling arbitrary TCP traffic relay and access to restricted destinations.