WinVNC installs the WinVNC3 registry key with permissions that give Special Access (read and modify) to the Everybody group, which allows users to read and modify sensitive information such as passwords and gain access to the system.

Buffer overflow in AT&T WinVNC (Virtual Network Computing) client 3.3.3r7 and earlier allows remote attackers to execute arbitrary commands via a long rfbConnFailed packet with a long reason string.

Buffer overflow in AT&T WinVNC (Virtual Network Computing) server 3.3.3r7 and earlier allows remote attackers to execute arbitrary commands via a long HTTP GET request when the DebugLevel registry key is greater than 0.

WinVNC 3.3.3 and earlier generates the same challenge string for multiple connections, which allows remote attackers to bypass VNC authentication by sniffing the challenge and response of other users.

Vulnerability in VNC, TightVNC, and TridiaVNC allows local users to execute arbitrary code as LocalSystem by using the Win32 Messaging System to bypass the VNC GUI and access the "Add new clients" dialogue box.