TROJ_JUNIDOR.MS
Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)
Threat Type: Trojan
Destructiveness: No
Encrypted: Yes
In the wild: Yes
OVERVIEW
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
172,032 bytes
EXE
Yes
30 Jul 2014
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 files:
- %User Temp%\self.bat - runs DFCheck service
- %User Temp%\~temp8520.tmp.tmp
- %User Temp%\kit.exe - copy of %System%\cmd.exe
(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, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.. %System% is the Windows system folder, which is usually C:\Windows\System32.)
Autostart Technique
This Trojan registers itself as a system service to ensure its automatic execution at every system startup by adding the following registry entries:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\DFCheck
ImagePath = "{malware path and filename}"
It registers as a system service to ensure its automatic execution at every system startup by adding the following registry keys:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\DFCheck
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Enum\Root\LEGACY_DFCHECK
Other System Modifications
This Trojan creates the following registry entry(ies) to bypass Windows Firewall:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
{malware path and filename} = "{malware path and filename}:*:Enabled:Distributed File Check"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\GloballyOpenPorts\
List
{port}:TCP = "{port}:TCP:*:Enabled:TCP_{port}"
Other Details
This Trojan does the following:
- It is a console application that may accept arguments that may be passed from another application or directly passed by malicious user if system is compromised.It may accept any of the following arguments:
- -i to install itself as DFCheck service
- -v identifies the installed version
- -t runs DFCheck service
- -u uninstall itself
- -m to modify connections (values: add, modify or del)
- -s to connect or listen (values: connect or listen)
- -h to specify IP address for connection
- -p to specify port for connection
- -d to test port
- By accepting arguments, it is capable of doing any of the following:
- Download and execute arbitrary files from specified URL by attacker
- Connect to remote IP addresses and port specified by attacker
- It connects to apk.{BLOCKED}catalog.net to report its infection.
NOTES:
It starts the following service :
- DFCheck
SOLUTION
9.700
10.952.07
29 Jul 2014
10.953.00
29 Jul 2014
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
Scan your computer with your Trend Micro product and note files detected as TROJ_JUNIDOR.MS
Step 4
Restart in Safe Mode
Step 5
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\SYSTEM\CurrentControlSet\Services\DFCheck
- ImagePath = "{malware path and filename}"
- ImagePath = "{malware path and filename}"
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\AuthorizedApplications\List
- {malware path and filename} = "{malware path and filename}:*:Enabled:Distributed File Check"
- {malware path and filename} = "{malware path and filename}:*:Enabled:Distributed File Check"
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\GloballyOpenPorts\List
- {port}:TCP = "{port}:TCP:*:Enabled:TCP_{port}"
- {port}:TCP = "{port}:TCP:*:Enabled:TCP_{port}"
Step 6
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. Before you could do this, you must restart in Safe Mode. For instructions on how to do this, you may refer to this page If the preceding step requires you to restart in safe mode, you may proceed to edit the system registry.
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
- DFCheck
- DFCheck
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum\Root
- LEGACY_DFCHECK
- LEGACY_DFCHECK
Step 7
Search and delete these files
- %User Temp%\self.bat
- %User Temp%\~temp8520.tmp.tmp
- %User Temp%\kit.exe
Step 8
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_JUNIDOR.MS. 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.