W32/AntiHost-A is a worm for the Windows platform.
When first run W32/AntiHost-A copies itself to <System>\ahr.exe.
The following registry entry is created to run ahr.exe on startup:
HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
antihost
<System>\ahr.exe
W32/AntiHost-A spreads by copying itself with the hidden filename antihost.exe to any mounted removable media. The hidden file autorun.inf is also created so that W32/AntiHost-A is automatically executed. This file can be safely deleted.