DDoS.Win32.NITOL.MKH
W32/ServStart.AM!tr(FORTINET), Backdoor.Nitol(NORTON)
Windows
Threat Type: DDoS malware
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
This DDoS malware 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
46,080 bytes
DLL
No
Arrival Details
This DDoS malware 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 DDoS malware adds the following folders:
- %User Temp%\IR{Random Characters}.tmp\
(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 drops the following files:
- %User Temp%\hrl{Random Characters}.tmp
- %System%\hyfzag.exe
- %User Temp%\SOFTWARE.LOG
- {Infected Directory}\lpk.dll → copy of itself
(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.)
It adds the following processes:
- %User Temp%\hrl{Random Characters}.tmp
- %System%\hyfzag.exe
- %System%\sc.exe start w32time task_started
- %System%\svchost.exe -k netsvcs
- find /i "lpk.dll"
- "%ProgramFiles%\WinRAR\rar.exe" x "{Fullpath of zip/rar file}" *.exe "%User Temp%\IR{Random Characters}.tmp\"
- cmd /c RD /s /q "%User Temp%\IR{Random Characters}.tmp"
- cmd /c %ProgramFiles%\WinRAR\rar.exe vb "{Fullpath of zip/rar file}" lpk.dll|find /i "lpk.dll"
- "%Program Files%\WinRAR\rar.exe" a -r -ep1"%User Temp%\IRA740.tmp" "{Fullpath of zip/rar file}" "%User Temp%\IRA740.tmp\lpk.dll"
(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.. %Program Files% is the default Program Files folder, usually C:\Program Files in Windows 2000(32-bit), Server 2003(32-bit), XP, Vista(64-bit), 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit) , or C:\Program Files (x86) in Windows XP(64-bit), Vista(64-bit), 7(64-bit), 8(64-bit), 8.1(64-bit), 2008(64-bit), 2012(64-bit) and 10(64-bit).)
Other System Modifications
This DDoS malware deletes the following files:
- %User Temp%\hrl{Random Characters}.tmp
- %User Temp%\SOFTWARE.LOG
(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).)
Adware Routine
This DDoS malware adds and runs the following services:
- Service Name: Distribulfs
Display Name: Distribulhq Transaction Coordinator Service
Start Type: SERVICE_AUTO_START
Binary Pathname: %System%\hyfzag.exe
(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)
Other Details
This DDoS malware does the following:
- Drops copy of itself to all directories in all drives except system drives.
- Finds zip or rar files then finds .exe files inside the compressed file, if found, does the following:
- copy the .exe file to %User Temp%\IR{Random Characters}.tmp\ directory.
- insert copy of itself(lpk.dll) in the compressed file.
(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).)
SOLUTION
9.800
17.338.02
25 Jan 2022
17.339.00
26 Jan 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
Restart in Safe Mode
Step 4
Disable this malware service
-
- Distribulfs
Step 5
Search and delete this file
- %User Temp%\hrl{Random Characters}.tmp
- %System%\hyfzag.exe
- %User Temp%\SOFTWARE.LOG
- {Infected Directory}\lpk.dll
Step 6
Search and delete this folder
- %User Temp%\IR{Random Characters}.tmp\
Step 7
Restart in normal mode and scan your computer with your Trend Micro product for files detected as DDoS.Win32.NITOL.MKH. 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.
Did this description help? Tell us how we did.