BKDR_POISON.TUHB
Windows
Threat Type: Backdoor
Destructiveness: No
Encrypted: Yes
In the wild: Yes
OVERVIEW
Downloaded from the Internet, Dropped by other malware
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 does not have any propagation routine.
It executes commands from a remote malicious user, effectively compromising the affected system.
TECHNICAL DETAILS
34,304 bytes
DLL
Yes
19 Jan 2017
Compromises system security
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 mutexes to ensure that only one of its copies runs at any one time:
- NIUJhUGIY
Autostart Technique
This backdoor adds the following registry entries to enable its automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\{GUID}
StubPath = "{malware path and filename}"
Propagation
This backdoor does not have any propagation routine.
Backdoor Routine
This backdoor executes the following commands from a remote malicious user:
- Send system information (Lan IP, Wan IP, Computer name, Username, Account Type, OS)
- Send hardware information (CPU speed, Memory)
- Manage Files (Search, Download, Upload, Execute, Rename, Delete)
- Manage Registries (Search, Modify, Delete, Rename, Create)
- Manage Processes (View, Kill, Suspend, Unload Module)
- Manage Services (View, Start, Stop, Edit, Install, Uninstall)
- Manage Devices (View, Enable, Disable, Remove)
- Manage Windows
- Relay server
- View,copy and uninstall applications
- View active ports
- Perform a shell command
- Download and inject remote codes to legitimate processes
- Log keystrokes and active window
- Capture screenshots
- View webcam activity
- Listen to microphone audio
- Update, Uninstall, Restart the malware
- Retrieve cached passwords and hashes
It connects to the following URL(s) to send and receive commands from a remote malicious user:
- film.{BLOCKED}ayfilmlink.com:443
Other Details
This backdoor requires the existence of the following files to properly run:
- {malware path}\McVsShld.exe - non malicious, used by the malware to load the malicious dll
- C:\Users\Public\Documents\yoshiDATA.dat - configuration file, also detected as BKDR_POISON.TUHB
NOTES:
It queries the default web browser by accessing the following registry entry: HKEY_CLASSES_ROOT\http\shell\open\command
It then launches a hidden Web browser process (e.g., iexplore.exe). The malware then injects its code to the said process, which contains its backdoor routines.
It does not have rootkit capabilities.
It does not exploit any vulnerability.
SOLUTION
9.8
13.166.06
19 Jan 2017
13.167.00
20 Jan 2017
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
Restart in Safe Mode
Step 3
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\SOFTWARE\Microsoft\Active Setup\Installed Components\{GUID}
- StubPath = "{malware path and filename}"
- StubPath = "{malware path and filename}"
Step 4
Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_POISON.TUHB. 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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