Threat Description



Category: Malware
Type: Virus
Platform: W32
Aliases: Purcyst


This is a boot virus. One unusual feature of this virus is that it infects both MBR and DBR on hard drives.

This virus also modified the CMOS settings of the machine in order to spoof a clean boot. Check that your drive A: settings are correct in CMOS Setup before booting clean and disinfecting the virus.

The code of the virus contains this text:


Otherwise the virus only spreads.


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.

Description Details: Mikko Hypponen, F-Secure


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