PIA's `POST /v1/upload/sbom` endpoint accepts a Bearer JWT and checks its **unverified** `iss` claim against an issuer allowlist using Python's `urlparse` before performing OIDC discovery with `requests`. Because `urlparse` and `requests`/`urllib3` parse an authority string containing a backslash (e.g. `https://attacker-host\@ci.eclipse.org/`) into *different* hostnames, an attacker can craft an issuer that passes the allowlist check yet drives `requests` — and subsequently `urllib.request.urlopen` for JWKS retrieval — to connect to an arbitrary attacker-chosen host, port, and scheme.
Server-Side Request Forgery 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.