BKDR_GEEKEY.A
Windows
Threat Type: Backdoor
Destructiveness: No
Encrypted: No
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 executes commands from a remote malicious user, effectively compromising the affected system. However, as of this writing, the said sites are inaccessible.
It modifies the Internet Explorer Zone Settings.
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 adds the following processes:
- msiexec.exe
It injects codes into the following process(es):
- created msiexec.exe
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\
Services\CryptService
ImagePath = {malware path}\wsc.exe
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\CryptService
DisplayName = Cryptographic Service
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\CryptService
Description = “Provides three management services: Catalog Database Service, which confirms the signatures of Windows files and allows new programs to be installed; If this service is disabled, any services that explicitly depend on it will fail to start”
Backdoor Routine
This Backdoor executes the following commands from a remote malicious user:
- Get list of drives
- Get list of files/folder
- Perform File operation (copy, move, rename, delete)
- Create directory
- Download File
- Upload File
- Execute files
It connects to the following URL(s) to send and receive commands from a remote malicious user:
- http://support.{BLOCKED}ization.org:443
However, as of this writing, the said sites are inaccessible.
Web Browser Home Page and Search Page Modification
This Backdoor modifies the Internet Explorer Zone Settings.
Other Details
This Backdoor requires the existence of the following files to properly run:
- {malware path}\data.bin <- malicious encrypted component file
- {malware path}\wsc.exe <- non-malicious, loads the dll component
It does the following:
- It queries the data of the following registry entry to decrypt the payload component:
- HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Cryptography\MachineGUID
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
Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.
Step 3
Restart in Safe Mode
Step 4
Delete this registry key
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_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
- CryptService
- CryptService
Step 5
Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_GEEKEY.A. 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.
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