TROJ64_WOWLIK.VT
TR/Crypt.XPACK.Gen (Avira)
Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)
Threat Type: Trojan
Destructiveness: No
Encrypted: Yes
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
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 injects codes into the following process(es):
- %Windows%\explorer.exe
- %System%\dllhost.exe
(Note: %Windows% is the Windows folder, which is usually C:\Windows.. %System% is the Windows system folder, which is usually C:\Windows\System32.)
Autostart Technique
This Trojan adds the following registry entries to enable its automatic execution at every system startup:
HKEY_CURRENT_USER\Software\Classes\
clsid\{fbeb8a05-beee-4442-804e-409d6c4515e9}\inprocserver32
[Default] = "\\?\globalroot\Device\{Harddisk volume #}\{malware path}\{malware name}"
HKEY_CLASSES_ROOT\CLSID\{fbeb8a05-beee-4442-804e-409d6c4515e9}\
InProcServer32
[Default] = "\\?\globalroot\Device\{Harddisk volume #}\{malware path}\{malware name}"
(Note: The default value data of the said registry entry is %System%\SHELL32.dll.)
Other Details
This Trojan connects to the following possibly malicious URL:
- http://{URL declared in 'wow.ini'}/cmd?version=1.5&aid={value}&id={GUID}&os={OS version}_{service pack}_{architecture}
It requires the existence of the following files to properly run:
- wow.ini
NOTES:
This Trojan sets the attribute of itself to Hidden.
This Trojan may connect to the URLs declared wow.ini for the following purposes:
- Update the configuration file
- Update itself
- Load additional modules
SOLUTION
Step 1
Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.
Step 2
Identify and delete files detected as TROJ64_WOWLIK.VT using either the Startup Disk or Recovery Console
Step 3
Delete this registry value
Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.
- In HKEY_CURRENT_USER\Software\Classes\clsid\{fbeb8a05-beee-4442-804e-409d6c4515e9}\inprocserver32
- [Default] = "\\?\globalroot\Device\{Harddisk volume #}\{malware path}\{malware name}"
- [Default] = "\\?\globalroot\Device\{Harddisk volume #}\{malware path}\{malware name}"
Step 4
Restore this modified registry value
Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.
- In HKEY_CLASSES_ROOT\CLSID\{fbeb8a05-beee-4442-804e-409d6c4515e9}\InProcServer32
- From: [Default] = "\\?\globalroot\Device\{Harddisk volume #}\{malware path}\{malware name}"
To: [Default] = "%System%\SHELL32.dll"
- From: [Default] = "\\?\globalroot\Device\{Harddisk volume #}\{malware path}\{malware name}"
Step 5
Scan your computer with your Trend Micro product to delete files detected as TROJ64_WOWLIK.VT. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.
Did this description help? Tell us how we did.