CVE-2026-53551 free5GC AUSF: null byte injection in supiOrSuci causes HTTP 500 internal service failure

free5GC is an open-source implementation of the 5G core network. Prior to 1.4.5, the free5GC AUSF Authentication Server Function does not validate the supiOrSuci field in UE authentication requests. Null bytes \x00 and other control characters pass through JSON parsing unchanged and are forwarded...