TROJ_JAKU.C
Backdoor.Win32.Poison.hrtw (Kaspersky); Trojan:Win32/Skeeyah.A!bit (Microsoft); Trojan.Asprox.B (Symantec)
Windows
Threat Type: Trojan
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
Dropped by other malware, Downloaded from the Internet
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.
It connects to certain websites to send and receive information. However, as of this writing, the said sites are inaccessible. It deletes the initially executed copy of itself.
TECHNICAL DETAILS
311,237 bytes
EXE
No
02 Oct 2015
Drops files, Deletes files, Downloads files, Connects to URLs/IPs
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:
- %Program Files%\Common Files\Services\CompSvc.exe
(Note: %Program Files% is the Program Files folder, where it usually is C:\Program Files on all Windows operating system versions; C:\Program Files (x86) for 32-bit applications running on Windows 64-bit operating systems.)
It drops the following files:
- %User Temp%\{Random}.txt -> contains stolen information
- %User Temp%\{Random}.ifo -> gzip compressed file of {Random}.txt
- %System%\sysprep\cryptbase.dll -> used for escalating permissions (if not admin)
- %User Temp%\{Random Name}.dll -> copy of cryptbase.dll (if not admin)
(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.. %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)
It drops and executes the following files:
- %Program Files%\Common Files\Services\SvcStart.exe
(Note: %Program Files% is the Program Files folder, where it usually is C:\Program Files on all Windows operating system versions; C:\Program Files (x86) for 32-bit applications running on Windows 64-bit operating systems.)
It adds the following processes:
- explorer.exe
- "%Program Files%\Common Files\Services\SvcStart.exe" R2D2{Malware Location}\{Malware Name}.exe
- %System%\sysprep\sysprep.exe -> used for escalating permissions (if not admin)
(Note: %Program Files% is the Program Files folder, where it usually is C:\Program Files on all Windows operating system versions; C:\Program Files (x86) for 32-bit applications running on Windows 64-bit operating systems.. %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)
It injects codes into the following process(es):
- created explorer.exe -> used to execute its routines (terminated afterwards)
Autostart Technique
This Trojan creates the following registry entries to enable automatic execution of dropped component at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\{4C2830A1-7D22-4f20-ADA2-3901BD61DDE4}
StubPath = "%Program Files%\Common Files\Services\SvcStart.exe"
Other System Modifications
This Trojan deletes the following files:
- %System%\sysprep\cryptbase.dll
- %User Temp%\{Random Name}.dll
(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.. %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)
Download Routine
This Trojan downloads the file from the following URL and renames the file when stored in the affected system:
- http://{BLOCKED}.{BLOCKED}.68.5/bbs/CaC.php
It saves the files it downloads using the following names:
- %User Temp%\tmp{4 Random Characters}.tmp
(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)
Information Theft
This Trojan gathers the following data:
- Computer Name
- OS Version
- IP Address
- Domain Name
Other Details
This Trojan connects to the following website to send and receive information:
- http://{BLOCKED}.{BLOCKED}.68.5/bbs/CaC.php
It does the following:
- SvcStart.exe could use the following arguments:
- SvcStart.exe R2D2{File}
- delete {File}
- SvcStart.exe R2D3{File}
- drop and execute exp.bat
- exp.bat does the following:
- delete {File}
- delete SvcStart.exe
- delete itself
- SvcStart.exe R2D2{File}
- It uses the following AntiAV techniques:
- Searches for the following Mutex to check if Bitdefender is installed:
- BDAgent-oneinstance-mutex
- Searches for the following Event to check if AVG is installed:
- AVG{53036606-6F17-41a9-80DD-AB930D6BA4DD}
- Searches for the following Mutex to check if Bitdefender is installed:
However, as of this writing, the said sites are inaccessible.
It deletes the initially executed copy of itself
SOLUTION
9.850
14.224.01
30 Apr 2018
14.225.00
01 May 2018
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
Identify and terminate files detected as TROJ_JAKU.C
- Windows Task Manager may not display all running processes. In this case, please use a third-party process viewer, preferably Process Explorer, to terminate the malware/grayware/spyware file. You may download the said tool here.
- If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
- If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.
Step 4
Delete this registry value
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\SOFTWARE\Microsoft\Active Setup\Installed Components\{4C2830A1-7D22-4f20-ADA2-3901BD61DDE4}
- StubPath = "%Program Files%\Common Files\Services\SvcStart.exe"
- StubPath = "%Program Files%\Common Files\Services\SvcStart.exe"
Step 5
Search and delete these files
- %Program Files%\Common Files\Services\SvcStart.exe
- %User Temp%\exp.bat
- %User Temp%\{Random}.txt
- %User Temp%\{Random}.ifo
- %System%\sysprep\cryptbase.dll
- %User Temp%\{Random Name}.dll
Step 6
Scan your computer with your Trend Micro product to delete files detected as TROJ_JAKU.C. 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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