WORM_SOHANAD.AC
Worm:AutoIt/YahLover.R (Microsoft); [.au3]:W32/Yahlover.worm.gen.c (McAfee); PAK:UPX, ARC:Embedded, [script.au3]:IM-Worm.Win32.Sohanad.cq (Kaspersky); Trojan.Win32.AutoIt.gen.1 (v) (Sunbelt); Worm.Generic.66307 (FSecure)
Windows 2000, Windows XP, Windows Server 2003
Threat Type: Worm
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
This worm arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
It disables Task Manager, Registry Editor, and Folder Options.
TECHNICAL DETAILS
181,849 bytes
EXE
Yes
14 May 2012
Arrival Details
This worm arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
Autostart Technique
This worm adds the following registry entries to enable its automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
Task Manager = "%Windows%\svhost32.exe"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
SVCHOST = "%Windows%\svhost.exe"
Other System Modifications
This worm adds the following registry keys:
HKEY_CURRENT_USER\Software\Policies\
Microsoft\Internet Explorer\Control Panel
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
System
HKEY_CURRENT_USER\Software\Yahoo\
pager\View\YMSGR_buzz
HKEY_CURRENT_USER\Software\Yahoo\
pager\View\YMSGR_Launchcast
It adds the following registry entries:
HKEY_CURRENT_USER\Software\Policies\
Microsoft\Internet Explorer\Control Panel
Homepage = "1"
HKEY_CURRENT_USER\Software\Yahoo\
pager\View\YMSGR_buzz
content url = "http://{BLOCKED}al-news.com"
HKEY_CURRENT_USER\Software\Yahoo\
pager\View\YMSGR_Launchcast
content url = "http://{BLOCKED}al-news.com"
It modifies the following registry entries:
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
Start Page = "http://{BLOCKED}al-news.com"
(Note: The default value data of the said registry entry is http://www.microsoft.com/isapi/redir.dll?prd=ie&pver=6&ar=msnhome.)
It creates the following registry entry(ies) to disable Task Manager, Registry Tools and Folder Options:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
System
DisableTaskMgr = "1"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
System
DisableRegistryTools = "1"
Dropping Routine
This worm drops the following files:
- %Windows%\svhost32.exe
- %Windows%\svhost.exe
(Note: %Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.)
Other Details
This worm connects to the following possibly malicious URL:
- http://termex.{BLOCKED}w.com/host.exe
- http://termex.{BLOCKED}w.com/host2.exe
This report is generated via an automated analysis system.
SOLUTION
9.200
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
Enable Registry Editor, Task Manager, and Folder options
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\Policies\Microsoft\Internet Explorer
- Control Panel
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies
- System
- In HKEY_CURRENT_USER\Software\Yahoo\pager\View
- YMSGR_buzz
- In HKEY_CURRENT_USER\Software\Yahoo\pager\View
- YMSGR_Launchcast
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_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
- Task Manager = "%Windows%\svhost32.exe"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
- SVCHOST = "%Windows%\svhost.exe"
- In HKEY_CURRENT_USER\Software\Policies\Microsoft\Internet Explorer\Control Panel
- Homepage = "1"
- In HKEY_CURRENT_USER\Software\Yahoo\pager\View\YMSGR_buzz
- content url = "http://{BLOCKED}al-news.com"
- In HKEY_CURRENT_USER\Software\Yahoo\pager\View\YMSGR_Launchcast
- content url = "http://{BLOCKED}al-news.com"
Step 6
Restore this modified 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\Internet Explorer\Main
- From: Start Page = "http://{BLOCKED}al-news.com"
To: Start Page = ""http://www.microsoft.com/isapi/redir.dll?prd=ie&pver=6&ar=msnhome""
- From: Start Page = "http://{BLOCKED}al-news.com"
Step 7
Search and delete these files
- %Windows%\svhost32.exe
- %Windows%\svhost.exe
Step 8
Restart in normal mode and scan your computer with your Trend Micro product for files detected as WORM_SOHANAD.AC. 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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