The genuine winhost.exe file is a software component of W32.Beagle.CL/K@mm Worm.
"winhost.exe" is a falsifying file in Windows, posing as a legitimate Windows file with its name, icon, and false developer name labeled as Microsoft. The file is a Trojan virus that claims to be the Windows Host Support Service. It runs in the background, displaying pop-ups and pop-unders on the screen that display sexual-themed images. It has also been reported that it opens the doorway to more viruses, which leads to very slow system speeds or frozen system operations.
WinHost stands for Windows Host
The .exe extension on a filename indicates an executable file. Executable files may, in some cases, harm your computer. Therefore, please read below to decide for yourself whether the winhost.exe on your computer is a Trojan that you should remove, or whether it is a file belonging to the Windows operating system or to a trusted application.
Description: Winhost.exe is not essential for Windows and will often cause problems. Winhost.exe is located in a subfolder of "C:\Program Files".
Known file sizes on Windows 10/8/7/XP are 232,448 bytes (85% of all occurrences) or 7,926,436 bytes.
There is no description of the program. The program has no visible window. Winhost.exe is not a Windows core file. The application uses ports to connect to or from a LAN or the Internet. Winhost.exe is able to monitor applications. Therefore the technical security rating is 85% dangerous, however you should also read the user reviews.
Recommended: Identify winhost.exe related errors
If winhost.exe is located in the C:\Windows\System32 folder, the security rating is 92% dangerous. The file size is 60,416 bytes (40% of all occurrences), 1,220,608 bytes or 704,512 bytes. Winhost.exe is a file with no information about its developer. The program has no visible window. It is located in the Windows folder, but it is not a Windows core file. The application is loaded during the Windows boot process (see Registry key: MACHINE\Run, Run, MACHINE\RunServices, Winlogon\Shell). It is not a Windows system file. Winhost.exe is able to record keyboard and mouse inputs, hide itself, manipulate other programs and monitor applications.
If winhost.exe is located in the C:\Windows folder, the security rating is 72% dangerous. The file size is 548,864 bytes (25% of all occurrences), 36,864 bytes, 517,468 bytes or 78,849 bytes. There is no file information. Winhost.exe is not a Windows system file. Winhost.exe is an unknown file in the Windows folder. The program is not visible. The process starts when Windows starts (see Registry key: MACHINE\Run, Run, MACHINE\RunServices, Winlogon\Shell). Winhost.exe is able to record keyboard and mouse inputs, hide itself, monitor applications and manipulate other programs.
If winhost.exe is located in C:\, the security rating is 82% dangerous. The file size is 32,256 bytes (33% of all occurrences), 47,616 bytes or 30,720 bytes.
If winhost.exe is located in a subfolder of the user's profile folder, the security rating is 59% dangerous. The file size is 168,960 bytes (33% of all occurrences), 68,608 bytes or 450,626 bytes.
If winhost.exe is located in a subfolder of C:\Windows, the security rating is 72% dangerous. The file size is 1,688,723 bytes.
If winhost.exe is located in a subfolder of the user's "Documents" folder, the security rating is 40% dangerous. The file size is 183,296 bytes.
External information from Paul Collins:
There are different files with the same name:
Important: Some malware also uses the file name winhost.exe, for example Trojan.Win32.Agent.arng or Trojan.Win32.Agent.msd (detected by Kaspersky), and Bitcoin Miner (detected by Sophos). Therefore, you should check the winhost.exe process on your PC to see if it is a threat. We recommend Security Task Manager for verifying your computer's security. This was one of the Top Download Picks of The Washington Post and PC World.
A clean and tidy computer is the key requirement for avoiding problems with winhost. This means running a scan for malware, cleaning your hard drive using cleanmgr and sfc /scannow, uninstalling programs that you no longer need, checking for Autostart programs (using msconfig) and enabling Windows' Automatic Update. Always remember to perform periodic backups, or at least to set restore points.
Should you experience an actual problem, try to recall the last thing you did, or the last thing you installed before the problem appeared for the first time. Use the resmon command to identify the processes that are causing your problem. Even for serious problems, rather than reinstalling Windows, you are better off repairing of your installation or, for Windows 8 and later versions, executing the DISM.exe /Online /Cleanup-image /Restorehealth command. This allows you to repair the operating system without losing data.
To help you analyze the winhost.exe process on your computer, the following programs have proven to be helpful: Security Task Manager displays all running Windows tasks, including embedded hidden processes, such as keyboard and browser monitoring or Autostart entries. A unique security risk rating indicates the likelihood of the process being potential spyware, malware or a Trojan. Malwarebytes Anti-Malware detects and removes sleeping spyware, adware, Trojans, keyloggers, malware and trackers from your hard drive.