W32/Forbot-FX is a network worm with backdoor Trojan functionality for the Windows platform.
When first run, W32/Forbot-FX copies itself to the Windows system folder as sys32.exe and sets the following registry entries in order to run each time a user logs on:
W32/Forbot-FX also creates its own service named "Win32", with the display name "System Net".
Once installed, W32/Forbot-FX connects to a preconfigured IRC server and joins a channel from which an attacker can issue further commands. These commands can cause the infected machine to perform any of the following actions:
flood a remote host (by either ping or HTTP)
start a SOCKS4 proxy server
start an HTTP server
start an FTP server
portscan randomly-chosen IP addresses
execute arbitrary commands
steal information such as passwords and product keys
open remote shell access
The worm can spread to network shares protected by weak passwords, to unpatched machines affected by the LSASS vulnerability (see MS04-011) and through backdoors left open by the Troj/Optix Trojans.