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.
Based on the settings of your F-Secure security product, it will either move the file to the quarantine where it cannot spread or cause harm, or remove it.
A False Positive is when a file is incorrectly detected as harmful, usually because its code or behavior resembles known harmful programs. A False Positive will usually be fixed in a subsequent database update without any action needed on your part. If you wish, you may also:
Check for the latest database updates
First check if your F-Secure security program is using the latest updates, then try scanning the file again.
Submit a sample
After checking, if you still believe the file is incorrectly detected, you can submit a sample of it for re-analysis.
Note: If the file was moved to quarantine, you need to collect the file from quarantine before you can submit it.
Exclude a file from further scanning
If you are certain that the file is safe and want to continue using it, you can exclude it from further scanning by the F-Secure security product.
Note: You need administrative rights to change the settings.
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.