CVE-2026-44320 free5GC: NEF nnef-callback route group is unauthenticated; forged callback requests are accepted into the processing path

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the nnef-callback route group without inbound OAuth2/bearer-token authorization. A forged or arbitrary bearer token e.g. Authorization: Bearer not-a-real-token is enough to reach the SMF-callback...

CVE-2026-44320

Summary: CVE-2026-44320 affects free5GC’s NEF, specifically the nnef-callback route group, which mounts without inbound OAuth2/bearer-token authorization. A forged or arbitrary bearer token can reach the SMF-callback handler, allowing the callback body to be parsed and dispatched into NEF busines...