W32/Tilebot-BC is a worm and IRC backdoor Trojan for the Windows platform.
W32/Tilebot-BC spreads to other network computers by exploiting common buffer overflow vulnerabilities, including: LSASS (MS04-011), RPC-DCOM (MS04-012), PNP (MS05-039) and ASN.1 (MS04-007) and by copying itself to network shares protected by weak passwords.
W32/Tilebot-BC runs continuously in the background, providing a backdoor server which allows a remote intruder to gain access and control over the computer via IRC channels.
W32/Tilebot-BC includes functionality to:
- access the internet and communicate with a remote server via HTTP
- setup a SOCKS4 server
- steal information from the Windows Protected Storage including harvesting username and passwords from Microsoft Outlook Express
- act as a HTTP proxy redirecting internet traffic
- create new AOL Instant Messenger profiles
- sniff internet packets
- download files from the internet
- changes the Internet Explorer start page
When first run W32/Tilebot-BC copies itself to <Windows>\MSmedia.exe and creates the file <System>\rdriv.sys.
The file rdriv.sys is detected as Troj/Rootkit-W.
The file MSmedia.exe is registered as a new system driver service named "MicroSoft Media Tools", with a display name of "MicroSoft Media Tools" and a startup type of automatic, so that it is started automatically during system startup. Registry entries are created under:
HKLM\SYSTEM\CurrentControlSet\Services\MicroSoft Media Tools\
The file rdriv.sys is registered as a new system driver service named "rdriv", with a display name of "rdriv". Registry entries are created under:
HKLM\SYSTEM\CurrentControlSet\Services\rdriv\
W32/Tilebot-BC sets the following registry entries, disabling the automatic startup of other software:
HKLM\SYSTEM\CurrentControlSet\Services\Messenger
Start
4
HKLM\SYSTEM\CurrentControlSet\Services\RemoteRegistry
Start
4
HKLM\SYSTEM\CurrentControlSet\Services\TlntSvr
Start
4
Registry entries are set as follows:
HKLM\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate
DoNotAllowXPSP2
1
HKLM\SOFTWARE\Microsoft\Ole
EnableDCOM
N
HKLM\SYSTEM\CurrentControlSet\Control\Lsa
restrictanonymous
1
Registry entries are created under:
HKLM\SOFTWARE\Microsoft\Security Center\
HKLM\SOFTWARE\Policies\Microsoft\WindowsFirewall\DomainProfile\
HKLM\SOFTWARE\Policies\Microsoft\WindowsFirewall\StandardProfile\
The following patches for the operating system vulnerabilities exploited by W32/Tilebot-BC can be obtained from the Microsoft website:
MS04-011
MS04-012
MS05-039
MS04-007