BKDR_SHELL.NLT
Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)
![](/vinfo/imgFiles/legend.jpg)
Threat Type: Backdoor
Destructiveness: No
Encrypted: Yes
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 may be downloaded by other malware/grayware from remote sites.
It does not have any propagation routine.
It executes commands from a remote malicious user, effectively compromising the affected system.
It does not have any downloading capability.
TECHNICAL DETAILS
63,488 bytes
EXE
Yes
13 Aug 2013
Compromises system security, Connects to URLs/IPs, Collects system information, Steals information
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.
It may be downloaded by the following malware/grayware from remote sites:
- LNK_DLOADR.ILP
Installation
This backdoor drops the following copies of itself into the affected system:
- %All Users Profile%\intel.exe
- %System Root%\Users\All Users\intel.exe - Windows Vista or 7
(Note: %All Users Profile% is the All Users or Common profile folder, which is C:\Documents and Settings\All Users in Windows 2000, XP, and Server 2003, and C:\ProgramData in Windows Vista and 7.. %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)
It adds the following mutexes to ensure that only one of its copies runs at any one time:
- PST-2.0
Other System Modifications
This backdoor adds the following registry entries as part of its installation routine:
HKEY_CLASSES_ROOT\LOG
CLSID = "{hex values}"
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
LOG
CLSID = "{hex values}"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
intel = ""
It adds the following registry keys as part of its installation routine:
HKEY_CLASSES_ROOT\LOG
HKEY_CLASSES_ROOT\LOGPROXY
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
LOG
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
LOGPROXY
Propagation
This backdoor does not have any propagation routine.
Backdoor Routine
This backdoor executes the following commands from a remote malicious user:
- Perform remote shell execution
- File management
- Create directories
- Get drive information
- Get processor information
- Screen capture
It connects to the following URL(s) to send and receive commands from a remote malicious user:
- http://{BLOCKED}se.{BLOCKED}tingrecovery.net/{random hex values}FFFFFFFF.aspx
Download Routine
This backdoor does not have any downloading capability.
Information Theft
This backdoor gathers the following data:
- Computer Name
- OECMP
- User Name
NOTES:
It disables the firewall by executing in command prompt the line net stop SharedAccess.
It does not have rootkit capabilities.
It does not exploit any vulnerability.
SOLUTION
9.300
10.216.08
14 Aug 2013
10.217.00
15 Aug 2013
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
Remove malware/grayware files that dropped/downloaded BKDR_SHELL.NLT
- LNK_DLOADR.ILP
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. 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_CLASSES_ROOT
- LOG
- LOG
- In HKEY_CLASSES_ROOT
- LOGPROXY
- LOGPROXY
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes
- LOG
- LOG
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes
- LOGPROXY
- LOGPROXY
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\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
- intel = ""
- intel = ""
Step 6
Search and delete these files
- %All Users Profile%\intel.exe
- %System Root%\Users\All Users\intel.exe - Windows Vista or 7
Step 7
Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_SHELL.NLT. 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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