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 ERRORFAILEDSERVICECONTROLLERCONNECT 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.
Cisco Systems VPN Client IPSec Driver (CVPNDRVA.sys) 5.0.02.0090 allows local users to cause a denial of service (crash) by calling the 0x80002038 IOCTL with a small size value, which triggers memory corruption.
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.