CVE-2026-18353

Description

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.

References

• https://github.com/eclipse-csi/pia/security/advisories/GHSA-v249-9xjm-qhgf
• https://github.com/eclipse-csi/pia/security/advisories/GHSA-v249-9xjm-qhgf