arrow_back
search
close

Trojan.Win32.BREDOLAB.AA

October 25, 2022
 Analysis by: Jeffrey Francis Bonaobra
 Modified by: Carlos Villegas Madrid
 ALIASES:

Trojan.Win32.Injector (IKARUS)

 PLATFORM:

Windows

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:
 INFORMATION EXPOSURE:

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Downloaded from the Internet, Dropped by other malware


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

File Size:

1,547,776 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

09 Sep 2022

Payload:

Connects to URLs/IPs, Drops files

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

Minimum Scan Engine:

9.800

FIRST VSAPI PATTERN FILE:

17.810.05

FIRST VSAPI PATTERN DATE:

13 Sep 2022

VSAPI OPR PATTERN File:

17.811.00

VSAPI OPR PATTERN Date:

14 Sep 2022

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:


Did this description help? Tell us how we did.