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Published May 23, 2010 | Updated Sep 15, 2017

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HackTool:Win32/Evidpatch.A

Detected by Microsoft Defender Antivirus

Aliases: VirTool.Evidpatch.A (VirusBuster) HackTool.AB (AVG) Win32/Tool.EvID4226 (ESET) Not-A-Virus.Patch.TCPIP (Ikarus) HackTool/EvID (Panda) VirTool:Win32/Evidpatch.A (other)

Summary

HackTool:Win32/Evidpatch.A is a tool that modifies the Windows system file "TCPIP.SYS". It removes the security limits imposed on the default number of concurrent TCP connection attempts within a specific time period.

Manual removal is not recommended for this threat. To detect and remove this program and other unwanted software that may be installed in your computer, run a full-system scan with an up-to-date antispyware product such as the following:

For more information on antivirus software, see http://www.microsoft.com/windows/antivirus-partners/.

Additional remediation steps for Hacktool:Win32/Evidpatch.A

Hacktool:Win32/Evidpatch.A may make lasting changes to system files that will NOT be restored by detecting and removing this threat. To restore the system file "TCPIP.SYS", you need to restore "TCPIP.SYS" from backup.

HackTool:Win32/Evidpatch.A

Summary

What to do now

Additional remediation steps for Hacktool:Win32/Evidpatch.A

Technical information

Threat behavior

Prevention

Symptoms

System changes