TROJ_DLOADE.XXTTG
Trojan-Downloader.Win32.Agent.hesn (Kaspersky); Trojan horse Generic36.WBN (AVG)
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: 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
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 drops the following copies of itself into the affected system:
- %Program Files%\Microsoft Iyyuue\Dhyqrwh.exe
(Note: %Program Files% is the default Program Files folder, usually C:\Program Files in Windows 2000, Server 2003, and XP (32-bit), Vista (32-bit), and 7 (32-bit), or C:\Program Files (x86) in Windows XP (64-bit), Vista (64-bit), and 7 (64-bit).)
It creates the following folders:
- %Program Files%\Microsoft Iyyuue
- %Program Files%\AppPatch
(Note: %Program Files% is the default Program Files folder, usually C:\Program Files in Windows 2000, Server 2003, and XP (32-bit), Vista (32-bit), and 7 (32-bit), or C:\Program Files (x86) in Windows XP (64-bit), Vista (64-bit), and 7 (64-bit).)
Autostart Technique
This Trojan 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\Wssuig yaayccas
Other System Modifications
This Trojan adds the following registry entries:
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Wssuig yaayccas
ConnectGroup = "ĬÈÏ·Ö×é"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Wssuig yaayccas
Description = "¼à²âºÍ¼àÊÓÐÂÓ²¼þÉ豸²¢×Ô¶¯¸üÐÂÉ豸Çý¶¯¡£"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Wssuig yaayccas
MarkTime = "2014-07-29 17:29"
Dropping Routine
This Trojan drops the following files:
- %Program Files%\AppPatch\NetSyst69.dll
(Note: %Program Files% is the default Program Files folder, usually C:\Program Files in Windows 2000, Server 2003, and XP (32-bit), Vista (32-bit), and 7 (32-bit), or C:\Program Files (x86) in Windows XP (64-bit), Vista (64-bit), and 7 (64-bit).)
Other Details
This Trojan connects to the following possibly malicious URL:
- http://www.{BLOCKED}6.com/ads/NetSyst69.jpg
- http://user.{BLOCKED}e.qq.com/12345678
- {BLOCKED}74.4
- {BLOCKED}.8.104
- {BLOCKED}5.158.245
This report is generated via an automated analysis system.
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
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
- Wssuig yaayccas
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_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Wssuig yaayccas
- ConnectGroup = "ĬÈÏ·Ö×é"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Wssuig yaayccas
- Description = "¼à²âºÍ¼àÊÓÐÂÓ²¼þÉ豸²¢×Ô¶¯¸üÐÂÉ豸Çý¶¯¡£"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Wssuig yaayccas
- MarkTime = "2014-07-29 17:29"
Step 5
Search and delete this file
- %Program Files%\AppPatch\NetSyst69.dll
Step 6
Search and delete these folders
- %Program Files%\Microsoft Iyyuue
- %Program Files%\AppPatch
Step 7
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_DLOADE.XXTTG. 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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