BKDR_NFLOG.XC
Windows 2000, Windows XP, Windows Server 2003
Threat Type: Backdoor
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
Dropped by other malware, Downloaded from the Internet
This backdoor executes commands from a remote malicious user, effectively compromising the affected system.
TECHNICAL DETAILS
67,584 bytes
OCX
Yes
07 Sep 2012
Connects to URLs/IPs, Compromises system security
Arrival Details
This backdoor may be downloaded from the following remote sites:
- http://www.{BLOCKED}s.com/NfLog/Nfile.asp
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\IPRIP
Type = 20
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\IPRIP
Start = 2
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\IPRIP
ErrorControl = 1
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\IPRIP
ImagePath = %SystemRoot%\System32\svchost.exe -k netsvc
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\IPRIP
DisplayName = "IPv6 Stack Local Support"c
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\IPRIP
ObjectName = "LocalSystem"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\IPRIP
Description = "Net address translation for IPv6 Protocol"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\IPRIP\Parameters
ServiceDll = {Malware Path and File Name}
Other System Modifications
This backdoor adds the following registry entries:
HKEY_CURRENT_USER\Software\Microsoft\
Clock
HID = "{hex values}"
Backdoor Routine
This backdoor executes the following commands from a remote malicious user:
- Download files
- Perform remote shell
- Retrieve system information
- Update self
It connects to the following URL(s) to send and receive commands from a remote malicious user:
- http://www.{BLOCKED}s.com/NfLog/Nfile.asp
- http://www.{BLOCKED}s.com/NfLog/TTip.asp
- http://www.{BLOCKED}s.com/NfLog/NfStart.asp
- http://www.{BLOCKED}s.com/NfLog/NfHostInfo.asp
- http://www.{BLOCKED}s.com/NfLog/NfCommand.asp
- http://www.{BLOCKED}s.com/NfLog/Nfpredown.asp
- http://www.{BLOCKED}s.com/NfLog/NfUpda.asp
It posts the following information to its command and control (C&C) server:
- IP configuration
- Network statistics
- Running processes
- Running services
- System information
- List of files from the folder %userprofile%\recent\
Stolen Information
This backdoor saves the stolen information in the following file:
- %Temp%\$NtUninstallKB942388$
(Note: %Temp% is the Windows Temporary folder, which is usually C:\Windows\Temp or C:\WINNT\Temp.)
NOTES:
It reports system infection by sending IP address and infection time to the following URL via HTTP post:
- http://www.{BLOCKED}s.com/NfLog/NfStart.asp
SOLUTION
9.200
9.378.03
07 Sep 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
Restart in Safe Mode
Step 3
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
- IPRIP
- IPRIP
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_CURRENT_USER\Software\Microsoft\Clock
- HID = "{hex values}"
- HID = "{hex values}"
Step 5
Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_NFLOG.XC. 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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