BKDR_KULUOZ.QD
Luhe.Fiha.A(AVG), Trojan.Win32.Meredrop(Ikarus), Win32/Kryptik.BSQQ(Nod32)
Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)
Threat Type: Backdoor
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
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 connects to a website to send and receive information.
TECHNICAL DETAILS
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 a copy of itself in the following folders using different file names:
- %AppDataLocal%\{random filename}.exe
(Note: %AppDataLocal% is the Local Application Data folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local on Windows Vista and 7.)
Autostart Technique
This backdoor creates the following registry entries to enable automatic execution of dropped component at every system startup:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{Random Value} = "%AppDataLocal%\{Random Filename}.exe"
Other System Modifications
This backdoor adds the following registry keys:
HKEY_CURRENT_USER\Software\{Random Value}
It adds the following registry entries as part of its installation routine:
HKEY_CURRENT_USER\Software\{Random Value}
{Random} = "{Value}"
Backdoor Routine
This backdoor connects to the following websites to send and receive information:
- http://{BLOCKED}.{BLOCKED}.248.25:8080/{VAlue}
- http://{BLOCKED}.{BLOCKED}.232.99:8080/{VAlue}
- http://{BLOCKED}.{BLOCKED}.42.186:8080/{VAlue}
- http://{BLOCKED}.{BLOCKED}.213.112:8080/{VAlue}
- http://{BLOCKED}.{BLOCKED}.124.232:8080/{VAlue}
- http://{BLOCKED}.{BLOCKED}.55.22:443/{VAlue}
- http://{BLOCKED}.{BLOCKED}.142.87:8080/{VAlue}
- http://{BLOCKED}.{BLOCKED}.117.238:8080/{VAlue}
- http://{BLOCKED}.{BLOCKED}.131.164:8080/{VAlue}
- http://{BLOCKED}.{BLOCKED}.248.25:8080/{VAlue}
- http://{BLOCKED}.{BLOCKED}.148.190:443/{VAlue}
SOLUTION
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 BKDR_KULUOZ.QD
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_CURRENT_USER\Software
- {Random Value}
- {Random Value}
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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
- {Random Value} = "%AppDataLocal%\{Random Filename}.exe"
- {Random Value} = "%AppDataLocal%\{Random Filename}.exe"
Step 6
Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_KULUOZ.QD. 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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