Trojan.Win32.BREDOLAB.AA
Trojan.Win32.Injector (IKARUS)
Windows
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
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 adds the following processes:
- ReGSVr32 /S "xjlhlwa.d" → executes the dropped DLL file
It creates the following folders:
- %User Temp%\IXP000.TMP → deletes afterwards
(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local\Temp on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)
Other System Modifications
This Trojan adds the following registry entries as part of its installation routine:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\RunOnce
wextract_cleanup0 = C:\Windows\system32\advpack.dll,DelNodeRunDLL32 "%User Temp%\IXP000.TMP\"
It modifies the following registry entries:
HKEY_USERS\.DEFAULT\Software\
Microsoft\Windows\CurrentVersion\
Internet Settings\Connections
SavedLegacySettings = "{Hex Data}"
Dropping Routine
This Trojan drops the following files:
- %User Temp%\IXP000.TMP\TMP4351$.TMP → deletes afterwards
- %User Temp%\IXP000.TMP\xjlhlwa.d → deletes afterwards
(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local\Temp on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)
Download Routine
This Trojan connects to the following URL(s) to download its component file(s):
- http://{BLOCKED}.{BLOCKED}.139.111:8080/
Other Details
This Trojan accepts the following parameters:
- /Q → Silent mode for batch
- /T:{Path} → Specifies the working temporary directory
- /C or /C /T{Path} → Extract the files on specific directory
- /C:{CMD} → Ignore install command defined by the author
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
Scan your computer with your Trend Micro product to delete files detected as Trojan.Win32.BREDOLAB.AA. 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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