Because your browser does not support JavaScript you are missing out on on some great image optimizations allowing this page to load faster.

Microsoft Security Intelligence

Microsoft Security Intelligence

Cart

Sign in

Attention: We will be transitioning to a new AAD or Microsoft Entra ID from the week of May 20, 2024. In case your tenant requires admin consent, please refer to this document located at Overview of user and admin consent - Microsoft Entra ID | Microsoft Learn and grant access to App ID: 6ba09155-cb24-475b-b24f-b4e28fc74365 with graph permissions for Directory.Read.All and User.Read for continued access.

We're gradually updating threat actor names in our reports to align with the new weather-themed taxonomy. Learn about Microsoft threat actor names

Published Apr 06, 2010 | Updated Sep 15, 2017

Learn about other threats

Worm:Win32/Pykspa.C

Detected by Microsoft Defender Antivirus

Aliases: Trojan.Win32.Vilsel.piv (Kaspersky) W32/Pykse.A (Norman) BackDoor.Hackdoor.P (AVG) Win32/AutoRun.Agent.TG (ESET) W32/Pykse.worm (McAfee) W32.Pykspa.D (Trend Micro)

Summary

Worm:Win32/Pykspa.C is a worm that spreads via Skype messaging, Twitter, mapped drives and network shares. It contains a backdoor that allows it to execute arbitrary commands from a remote attacker.

Manual removal is not recommended for this threat. To detect and remove this threat and other malicious software that may have been installed, run a full-system scan with an up-to-date antivirus product such as Microsoft Security Essentials, or the Microsoft Safety Scanner. For more information about using antivirus software, see http://www.microsoft.com/security/antivirus/av.aspx.

Additional remediation instructions for Worm:Win32/Pykspa.C

This threat may make lasting changes to a computer’s configuration that are NOT restored by detecting and removing this threat. For more information on returning an infected computer to its pre-infected state, please see the following article/s:

Restoring your System Registry:

For Windows 7: http://windows.microsoft.com/en-us/windows7/Back-up-the-registry
For Windows Vista: http://windows.microsoft.com/en-US/windows-vista/Back-up-the-registry
For Windows XP: http://support.microsoft.com/kb/322756/

Resetting System Security Settings to default:

For Windows XP and Vista: http://support.microsoft.com/kb/313222

Stopping and starting Windows services:

For Windows 7: http://windows.microsoft.com/en-US/windows7/What-are-Administrative-Tools
For Windows Vista: http://windows.microsoft.com/en-US/windows-vista/What-are-Administrative-Tools
For Windows XP: http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/sys_srv_start_service.mspx

Enabling System Restore:

For Windows 7: http://windows.microsoft.com/en-us/windows7/What-is-System-Restore
For Windows Vista: http://windows.microsoft.com/en-us/windows-vista/What-is-System-Restore
For Windows XP: http://support.microsoft.com/kb/310405

Enabling Windows Firewall:

For Windows 7: http://windows.microsoft.com/en-US/windows7/Turn-Windows-Firewall-on-or-off
For Windows Vista: http://windows.microsoft.com/en-US/windows-vista/Turn-Windows-Firewall-on-or-off
For Windows XP: http://support.microsoft.com/kb/283673

Enabling Windows Security Center/Action Center alerts:

For Windows 7: http://windows.microsoft.com/en-us/windows7/What-happened-to-Windows-Security-Center
For Windows Vista: http://windows.microsoft.com/en-US/windows-vista/Using-Windows-Security-Center
For Windows XP: http://support.microsoft.com/kb/889737

Correctly disabling Autorun in Windows:

http://support.microsoft.com/kb/953252

Recreating a clean HOSTS file:

http://support.microsoft.com/kb/972034