Qbik WinGate, when transparent interception mode is enabled, uses the HTTP Host header to determine the remote endpoint, which allows remote attackers to bypass access controls for Flash, Java, Silverlight, and probably other technologies, and possibly communicate with restricted intranet sites, via a crafted web page that causes a client to send HTTP requests with a modified Host header.

Multiple implementations of the DNS protocol, including (1) Poslib 1.0.2-1 and earlier as used by Posadis, (2) Axis Network products before firmware 3.13, and (3) Men & Mice Suite 2.2x before 2.2.3 and 3.5.x before 3.5.2, allow remote attackers to cause a denial of service (CPU and network bandwidth consumption) by triggering a communications loop via (a) DNS query packets with localhost as a spoofed source address, or (b) a response packet that triggers a response packet.