is a generic host
process name for a group of services that are run from dynamic-link libraries (DLLs) and can run other services underneath itself. This is a valid system process that belongs to the Windows Operating System which handles processes executed from .dll's
. It runs from the registry key, HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\Svchost where details of the services running under each instance of svchost.exe can be found. At startup, Svchost.exe checks the services portion of the registry to construct a list of services that it needs to load. It is not unusual for multiple instances of Svchost.exe running at the same time
in Task Manager
in order to optimize the running of the various services.
svchost.exe SYSTEM (there can be more than one listed
svchost.exe LOCAL SERVICE
svchost.exe NETWORK SERVICE (there can be more than one listed
Each Svchost.exe session can contain a grouping of services, therefore, separate services can run, depending on how and where Svchost.exe is started. This grouping of services permits better control and easier debugging. The process ID's (PID's) are not static and can change with each logon but generally they stay nearly the same because they are running services all the time. The PID's must be checked in real time to determine what services each instance of svchost.exe is controlling at that particular time.
Determining whether a file is malware or a legitimate process sometimes depends on the location (path) it is running from. One of the ways that malware tries to hide is to give itself the same name as a critical system file like svchost.exe. However, it then places itself in a different location on your computer. Another techinique is for the process to alter the registry and add itself as a Startup program
so that it can run automatically each time the computer is booted. In XP, the legitimate Svchost.exe file is located in your C:\WINDOWS\system32\
Other legitimate copies can be found in the following folders:
There are several ways to investigate and see what services a Svchost.exe process is controlling and using Process Explorer is one of them. For a more detailed quide to using this tool, please refer to How to determine what services are running under a Svchost.exe process
Other tools to investigate running processes and gather additional information to identify them and resolve problems: