TROJ_COINMINE.WIOJ
Trojan:Win32/Adylkuzz.B (Microsoft), a variant of Win32/CoinMiner.AFR (NOD32), Trojan.CoinMiner (QUICKHEAL)
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
1,449,984 bytes
Yes
09 May 2017
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 drops the following copies of itself into the affected system and executes them:
- %Windows%\Prefetch\wuauser.exe
(Note: %Windows% is the Windows folder, where it usually is C:\Windows on all Windows operating system versions.)
Other System Modifications
This Trojan adds the following registry keys:
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\WELM
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\WELM\Security
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Enum\Root\LEGACY_WELM
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Enum\Root\LEGACY_WELM\
0000
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Enum\Root\LEGACY_WELM\
0000\Control
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\WELM\Enum
It adds the following registry entries as part of its installation routine:
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\WELM
Type = "16"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Enum\Root\LEGACY_WELM\
0000
ClassGUID = {GUID}
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Enum\Root\LEGACY_WELM\
0000
DeviceDesc = "Windows Event Log Management"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\WELM\Enum
0 = "Root\LEGACY_WELM\0000"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\WELM\Enum
Count = "1"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\WELM\Enum
NextInstance = "1"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\ServiceCurrent
(Default) = "16"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Enum\Root\LEGACY_WELM\
0000\Control
ActiveService = "WELM"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\WELM
Start = "2"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\WELM
ErrorControl = "0"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\WELM
ImagePath = "%Windows%\Prefetch\wuauser.exe --server"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\WELM
DisplayName = "Windows Event Log Management"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\WELM\Security
Security = {hex values}
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\WELM
ObjectName = "LocalSystem"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\WELM
FailureActions = {hex values}
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\WELM
Description = "Windows Provides Event Log to access management information."
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Enum\Root\LEGACY_WELM
NextInstance = "1"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Enum\Root\LEGACY_WELM\
0000\Control
*NewlyCreated* = "0"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Enum\Root\LEGACY_WELM\
0000
Service = "WELM"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Enum\Root\LEGACY_WELM\
0000
Legacy = "1"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Enum\Root\LEGACY_WELM\
0000
ConfigFlags = "0"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Enum\Root\LEGACY_WELM\
0000
Class = "LegacyDriver"
Dropping Routine
This Trojan drops the following files:
- %Windows%\Prefetch\id.txt
- %Temp%\{random}_Miner_.log
(Note: %Windows% is the Windows folder, where it usually is C:\Windows on all Windows operating system versions.. %Temp% is the Windows temporary folder, where it usually is C:\Windows\Temp on all Windows operating system versions.)
Download Routine
This Trojan saves the files it downloads using the following names:
- %Windows%\security\msiexev.exe
(Note: %Windows% is the Windows folder, where it usually is C:\Windows on all Windows operating system versions.)
Other Details
This Trojan connects to the following possibly malicious URL:
- {BLOCKED}7.{BLOCKED}566.com
- {BLOCKED}ip.com
SOLUTION
9.850
13.394.05
09 May 2017
13.395.00
10 May 2017
Step 1
Before doing any scans, Windows XP, Windows Vista, and Windows 7 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
Disable this malware service
- WELM
Step 4
Delete this registry key
Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services
- WELM
- WELM
Step 5
Search and delete this file
- %Windows%\security\msiexev.exe
- %Windows%\Prefetch\id.txt
- %Windows%\Temp\{random}_Miner_.log
Step 6
Scan your computer with your Trend Micro product to delete files detected as TROJ_COINMINE.WIOJ. 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.
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