BKDR_QAKBOT.XE
Windows 2000, Windows XP, Windows Server 2003
Threat Type: Backdoor
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
Downloaded from the Internet, Dropped by other malware
This backdoor arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
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 connects to a website to send and receive information.
It deletes the initially executed copy of itself.
TECHNICAL DETAILS
187,392 bytes
EXE
Yes
20 Oct 2012
Compromises system security, Connects to URLs/IPs
Arrival Details
This backdoor 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 backdoor drops the following file(s)/component(s):
- %Application Data%\Microsoft\Entdj\entdj32.dll - detected as TROJ_QBOTCFG.SM
- %Application Data%\Microsoft\Entdj\centdj32.dll - detected as TROJ_QBOTCFG.SM
(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Windows\Profiles\{user name}\Application Data on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Application Data on Windows NT, and C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, XP, and Server 2003.)
It drops the following copies of itself into the affected system:
- %Application Data%\Microsoft\Entdj\entdj.exe
(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Windows\Profiles\{user name}\Application Data on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Application Data on Windows NT, and C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, XP, and Server 2003.)
It drops the following non-malicious file:
- %Application Data%\Microsoft\Entdj\entd.dll
(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Windows\Profiles\{user name}\Application Data on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Application Data on Windows NT, and C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, XP, and Server 2003.)
It injects threads into the following normal process(es):
- wscntfy.exe
Autostart Technique
This backdoor 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\mpnhfn
Type = 10
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\mpnhfn
Start = 2
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\mpnhfn
ErrorControl = 0
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\mpnhfn
DisplayName = "Remote Procedure Call (RPC) Service"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\mpnhfn
DependOnService = Dnscache
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\mpnhfn
DependOnGroup = 00
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\mpnhfn
ObjectName = "LocalSystem"
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.
It connects to the following websites to send and receive information:
- {BLOCKED}istr.in
- {BLOCKED}vtkn.in.ua
Other Details
This backdoor connects to the following URL(s) to get the affected system's IP address:
- http://www.ip-adress.com/
- http://www.ipaddressworld.com/
It connects to the following possibly malicious URL:
- http://{BLOCKED}5.bluehost.com
- http://{BLOCKED}8.leavmauytdk.info/t
- http://www.{BLOCKED}edica.com/ac7.php
- http://www.{BLOCKED}y.com/
- http://www.{BLOCKED}onlyc.com/ac7.php
- http://www.{BLOCKED}agon.com/ac7.php
It deletes the initially executed copy of itself
SOLUTION
9.300
9.474.02
20 Oct 2012
9.475.00
21 Oct 2012
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 2
Remove malware files dropped/downloaded by BKDR_QAKBOT.XE
- TROJ_QBOTCFG.SM
Step 3
Restart in Safe Mode
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\CurrentControlSet\Services
- mpnhfn
- mpnhfn
Step 5
Search and delete this file
Step 6
Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_QAKBOT.XE. 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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