Threat description


Category: Malware
Type: Virus
Platform: W32
Aliases: Yesterday, YOM


Yesterday is a simple COM file infector. Every 128th time the virus is run it adjusts the computer's date backwards by one day.

The virus contains the texts '[pepper]' and 'yesterday once more'.


Automatic action

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


More information on scanning and removal options available in your F-Secure product can be found in the Help Center.

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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