TROJ_ZBOT.ALK
PWS:Win32/Zbot.gen!R (Microsoft), Infostealer.Banker.C (Symantec), Spy-Agent.bw.gen.i (McAfee), Trojan-Spy.Win32.Zbot.gen (Kaspersky)
Windows 2000, Windows XP, Windows Server 2003
Threat Type: Trojan
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
TECHNICAL DETAILS
Varies
EXE
Yes
15 Jan 2009
Modifies system registry, Drops files, Connects to URLs/Ips
Arrival Details
This Trojan 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 Trojan drops the following copies of itself into the affected system:
- %System%\twex.exe
(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.)
It drops the following files:
- %System%\twain32\local.ds
- %System%\twain32\user.ds
(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 Trojan modifies the following registry entries to ensure it automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Winlogon
Userinit = "%System%\userinit.exe,%System%\twex.exe"
(Note: The default value data of the said registry entry is %System%\userinit.exe,.)
Other System Modifications
This Trojan adds the following registry keys:
HKEY_USERS\.DEFAULT\Software\
Microsoft\Protected Storage System Provider
HKEY_USERS\.DEFAULT\Software\
Microsoft\Windows\CurrentVersion\
Explorer\{43BF8CD1-C5D5-2230-7BB2-98F22C2B7DC6}
It adds the following registry entries:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Network
UID = "{machine name}_{random hexadecimal number}"
Other Details
This Trojan connects to the following possibly malicious URL:
- http://{BLOCKED}3tr.org/iqato/mix2/cfg.bin