Threat Description



Category: Malware
Type: Virus
Platform: W32
Aliases: Lemming, Keeper


The first variant of this virus appears to have been written to force TBScan to use the DOS file system and ignore the contents of Anti-vir.dat. It is also known as the "Thunderbyte Killer" due to the text "The Rise and Fall of Thunderbyte-1994-Australia. You Will Never Trust Anti-Virus Software Again!!", but it also attempts to avoid detection by F-Secure anti-virus products and Norton Antivirus.

Lemming has been reported to be widespread in Australia.

There are few known variants.


Automatic action

Once detected, the F-Secure security product will automatically disinfect the suspect file by either deleting it or renaming it.

More scanning & removal options

More information on scanning or removal options is available in the documentation for your F-Secure security product on the Downloads section of our Home - Global site.

You may also refer to the Knowledge Base on the F-Secure Community site for more information.

Contact Support

For further assistance, F-Secure customers can request support online via the Request support or the Chat forms on our Home - Global site.


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