TROJ_BLYAME.SMEP
Trojan:Win32/Bamital.E (Microsoft); BackDoor-DKI.gen.bx (McAfee); Trojan.Bamital (Symantec); Trojan-Dropper.Win32.Drooptroop.aam (Kaspersky); Trojan.Win32.Bamital.G (v) (Sunbelt); Trojan.Dropper.Agent.UWS (FSecure)
Windows 2000, Windows XP, Windows Server 2003
Threat Type: Trojan
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
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.
TECHNICAL DETAILS
35,840 bytes
EXE
No
10 May 2012
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.
Installation
This Trojan creates the following folders:
- %Application Data%\Windows Server
(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.)
Other System Modifications
This Trojan adds the following registry keys:
HKEY_CURRENT_USER\Software\zkblyklrkg
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Control\Session Manager\AppCertDlls
It adds the following registry entries:
HKEY_CURRENT_USER\Software\zkblyklrkg
zkblyklrkg = "{random values}"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Session Manager\AppCertDlls
AppSecDll = "%Application Data%\Windows Server\yklrkg.dll"
It modifies the following registry entries:
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\sr\Parameters
FirstRun = "1"
Dropping Routine
This Trojan drops the following files:
- %Application Data%\Windows Server\yklrkg.dll
(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.)
This report is generated via an automated analysis system.
SOLUTION
9.200
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
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_CURRENT_USER\Software
- zkblyklrkg
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager
- AppCertDlls
Step 3
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\zkblyklrkg
- zkblyklrkg = "{random values}"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Session Manager\AppCertDlls
- AppSecDll = "%Application Data%\Windows Server\yklrkg.dll"
Step 4
Restore these modified registry values
Important:Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this only if you know how to or you can seek your system administrator's help. You may also check out this Microsoft article first before modifying your computer's registry.
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\sr\Parameters
- FirstRun = "1"
Step 5
Search and delete this file
- %Application Data%\Windows Server\yklrkg.dll
Step 6
Search and delete this folder
- %Application Data%\Windows Server
Step 7
Scan your computer with your Trend Micro product to delete files detected as TROJ_BLYAME.SMEP. 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.