Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)
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. It may be dropped by other malware.
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.
It may be dropped by the following malware:
Installation
This Trojan drops the following copies of itself into the affected system:
(Note: %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\{random}
DisplayName = "{random}"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\{random}
ErrorControl = "0"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\{random}
Group = "Boot Bus Extender"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\{random}
ImagePath = "%System%\drivers\{random}.sys"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\{random}
Start = "0"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\{random}
Tag = "1"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\{random}
Type = "1"
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\{random}
Rootkit Capabilities
This Trojan is used by other malware for its rootkit functionalities.
NOTES:
This Trojan disables services used by the following companies by modifying its code to return to unsuccessful status:
It disables drivers with the following names by modifying its code to return to unsuccessful status:
It has anti-virtual machine routine that causes virtual machines to hang.
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
Scan your computer with your Trend Micro product and note files detected as RTKT_NECURS.B
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.
Step 5
Search and delete files detected as RTKT_NECURS.B
Step 6
Restart in normal mode and scan your computer with your Trend Micro product for files detected as RTKT_NECURS.B. 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.
