BKDR_IRCBOT.CJC
Windows 2000, Windows, XP, Windows Server 2003
![](/vinfo/imgFiles/legend.jpg)
Threat Type: Backdoor
Destructiveness: No
Encrypted: Yes
In the wild: Yes
OVERVIEW
This backdoor arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
It deletes the initially executed copy of itself.
TECHNICAL DETAILS
Arrival Details
This backdoor arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
Installation
This backdoor drops the following copies of itself into the affected system:
- %Windows%\system\wmisvr.exe
(Note: %Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.)
It drops the following files:
- %System%\drivers\sysdrv32.sys
(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)
Autostart Technique
This backdoor registers itself as a system service to ensure its automatic execution at every system startup by adding the following registry entries:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Enum\Root\LEGACY_WMISRV\
0000
Service = "WMISRV"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\WMISRV
ImagePath = "%Windows%\system\wmisvr.exe"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\WMISRV
DisplayName = "WMI Servicer"
Other System Modifications
This backdoor adds the following registry keys:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Enum\Root\LEGACY_WMISRV
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Enum\Root\LEGACY_WMISRV\
0000
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\WMISRV
Other Details
This backdoor connects to the following possibly malicious URL:
- sec.{BLOCKED}icofskorea.info
It deletes the initially executed copy of itself