BKDR_VB.JMY
Windows 2000, XP, Server 2003
![](/vinfo/imgFiles/legend.jpg)
Threat Type: Backdoor
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
This backdoor may arrive bundled with malware packages as a malware component. It may be unknowingly downloaded by a user while visiting malicious websites.
It executes then deletes itself afterward.
It opens a random port to allow a remote user to connect to the affected system. Once a successful connection is established, the remote user executes commands on the affected system.
It executes the dropped file(s). As a result, malicious routines of the dropped files are exhibited on the affected system.
It executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system.
TECHNICAL DETAILS
Random
34,304 bytes
PE
Yes
27 Nov 2009
Drops files, Downloads files
Arrival Details
This backdoor may arrive bundled with malware packages as a malware component.
It may be unknowingly downloaded by a user while visiting malicious websites.
Installation
This backdoor drops the following copies of itself into the affected system:
- %User Temp%\202fbh.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.)
It drops the following file(s)/component(s):
- %System%\msllhsjn.dll - detected as TSPY_ONLINEG.SMQ
(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)
It executes then deletes itself afterward.
Autostart Technique
This backdoor adds the following registry entries to enable its automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
Explorer\Run
a5x3tq = %User Temp%\202fbh.exe
Other System Modifications
This backdoor modifies the following registry key(s)/entry(ies) as part of its installation routine:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess
Start = 4
(Note: The default value data of the said registry entry is 2.)
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\wscsvc
Start = 4
(Note: The default value data of the said registry entry is 2.)
Backdoor Routine
This backdoor opens a random port to allow a remote user to connect to the affected system. Once a successful connection is established, the remote user executes commands on the affected system.
Dropping Routine
This backdoor executes the dropped file(s). As a result, malicious routines of the dropped files are exhibited on the affected system.
Download Routine
This backdoor accesses the following websites to download files:
- http://exe.{BLOCKED}texe.com:255/list.php?c={File Properties}
Trend Micro detects the dowloaded file as:
- TSPY_FRETHOG.SMZ
It then executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system.
Other Details
This backdoor does the following:
- attempts to establish a connection to the site {BLOCKED}.{BLOCKED}.127.203
SOLUTION
8.900
6.206.05
15 Jun 2009
7.245.00
15 Jun 2010
Step 1
For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.
Step 3
Terminate a process file/s detected as BKDR_VB.JMY
*Note: If the detected file/s is/are not displayed in theWindows Task Manager, 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\Windows\CurrentVersion\policies\Explorer\Run
- a5x3tq = %User Temp%\202fbh.exe
- a5x3tq = %User Temp%\202fbh.exe
Step 5
Restore this modified 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\SharedAccess
- From: Start = 4
To: 2
- From: Start = 4
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\wscsvc
- From: Start = 4
To: 2
- From: Start = 4
Step 6
Scan your computer with your Trend Micro product to delete files detected as BKDR_VB.JMY. 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.