Virus:W32/Tenga.A is a virus that infects all executable files. It spreads by integrating itself into more files each time the host program is run.
Once detected, the F-Secure security product will automatically disinfect the suspect file by either deleting it or renaming it.
More information on the scanning and removal options available in your F-Secure product can be found in the Help Center.
Tenga is a network-aware parasitic file infector virus. For full disinfection instructions for a local network, please Eliminating A Local Network Outbreak.
On executing the infected file, the virus attempts to contact a remote server and download and execute a file. In addition, the virus installs a remote command shell on the infected machine.
Tenga.A infects files by appending itself to each Windows executable file it finds. The virus also has the ability to scan the network and infect files found in open network shares.
It avoids infecting ntoskrnl.exe and marks each infected executable files with the character `V´ in the old DOS stub header. The marking of the infected files prevents re-infection attempts.
To check if an instance of itself is already running, the virus creates a mutex named gaelicum.
Upon execution, it connects to and tries to download and execute http://utenti.lycos.it/[***]/dl.exe
It also connects to http://[***].users.freebsd.at and opens a remote command shell on the affected machine on port 54321.
The virus uses CRC matching to search for the required APIs it needs to do its malicious tasks.
Tenga.A also elevates its privileges and disables Windows File Protection.
F-Secure Anti-Virus detects this malware with the following updates:
Detection Type: PC
Description Created: 2006-06-06 10:25:42.0
Description Last Modified: 2010-08-16 07:33:54.0