Trojan.JS.XWORM.D
Trojan.GenericFCA.10629 (BITDEFENDER)
Windows
Threat Type: Trojan
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
This Trojan arrives as attachment to mass-mailed email messages. It 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 does not have any backdoor routine.
It does not have any information-stealing capability.
TECHNICAL DETAILS
Arrival Details
This Trojan arrives as attachment to mass-mailed email messages.
It 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 files:
- %User Profile%\Documents\YAYBFBAOABHZZWJH.ttf → a Lua script file masquerading as a .ttf file (detected as TrojanSpy.MSIL.XWORM.B)
- %User Profile%\Documents\YAYBFBAOABHZZWJH.PIF → a LuaJIT executable masquerading as a .PIF file
It adds the following processes:
- %User Profile%\Documents\YAYBFBAOABHZZWJH.PIF %User Profile%\Documents\YAYBFBAOABHZZWJH.ttf → launches the LuaJIT executable to execute the obfuscated Lua script
(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name} on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)
Propagation
This Trojan does not have any propagation routine.
Backdoor Routine
This Trojan does not have any backdoor routine.
Rootkit Capabilities
This Trojan does not have rootkit capabilities.
Information Theft
This Trojan does not have any information-stealing capability.
Other Details
This Trojan does the following:
- Checks whether the dropped component files are already present in the Documents folder, and skips dropping its components when the files are found
- Launches the dropped component with a hidden window
- When the dropped lua script is executed through the interpreter, it loads a .NET assembly in memory as its payload that connects to its C2 server which sends and receives commands from a remote malicious user.
It does not exploit any vulnerability.
SOLUTION
Step 1
Before doing any scans, Windows 7, Windows 8, Windows 8.1, and Windows 10 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
Search and delete this file
- %User Profile%\Documents\YAYBFBAOABHZZWJH.ttf
- %User Profile%\Documents\YAYBFBAOABHZZWJH.PIF
Step 5
Restart in normal mode and scan your computer with your Trend Micro product for files detected as Trojan.JS.XWORM.D. 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.
Step 6
Scan your computer with your Trend Micro product to delete files detected as Trojan.JS.XWORM.D. 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 the following Trend Micro Support pages for more information:
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