Multiple vulnerabilities exist in the Cisco ASA 5500 Series Adaptive Security Appliances and Cisco PIX Security Appliances: 1) Windows NT domain authentication bypass; 2) IPv6 Denial of Service; and 3) Crypto Accelerator memory leak. NOTE: These vulnerabilities are independent of each other. A device may be affected by one vulnerability and not affected by another. The risk is MEDIUM. A remote intruder could make a VPN connection to a network without needing to authenticate.