Cisco VPN Client 5.x through 5.0.07.0440 uses weak permissions for vpnclient.ini, which allows local users to gain privileges by entering an arbitrary program name in the Command field of the ApplicationLauncher section.
The VPN driver in Cisco VPN Client on Windows does not properly interact with the kernel, which allows local users to cause a denial of service (kernel fault and system crash) via a crafted application, aka Bug ID CSCuc81669.
Untrusted search path vulnerability in Cisco VPN Client 5.0 allows local users to gain privileges via a Trojan horse DLL in the current working directory, aka Bug ID CSCua28747.
The StartServiceCtrlDispatcher function in the cvpnd service (cvpnd.exe) in Cisco VPN client for Windows before 5.0.06.0100 does not properly handle an ERROR_FAILED_SERVICE_CONTROLLER_CONNECT error, which allows local users to cause a denial of service (service crash and VPN connection loss) via a manual start of cvpnd.exe while the cvpnd service is running.
dne2000.sys in Citrix Deterministic Network Enhancer (DNE) 2.21.7.233 through 3.21.7.17464, as used in (1) Cisco VPN Client, (2) Blue Coat WinProxy, and (3) SafeNet SoftRemote and HighAssurance Remote, allows local users to gain privileges via a crafted DNE_IOCTL DeviceIoControl request to the \\.\DNE device interface.
Cisco VPN Client on Windows before 5.0.01.0600, and the 5.0.01.0600 InstallShield (IS) release, uses weak permissions for cvpnd.exe (Modify granted to Interactive Users), which allows local users to gain privileges via a modified cvpnd.exe.