freerdp: FreeRDP has a NULL Pointer Dereference in rdp_write_logon_info_v2()

A null pointer dereference has been discovered in FreeRDP. A NULL pointer dereference vulnerability in rdpwritelogoninfov2 allows a malicious RDP server to crash FreeRDP proxy by sending a specially crafted LogonInfoV2 PDU with cbDomain=0 or cbUserName=0...