MD5: 9a1780be75d21c610c81c6028441c8a4
SHA1: 1e29cc5311f580a8ca8baaed0108dbdd9c26df35
SHA256: 3fce5f702f072d73777b981ca9650d8c28350807b0e7acd028df31208edc1326
SSDeep: 24576:QgDhdkMRWfLTUO2Zu1um76EgDhdkMRWfLTUO2Zu1um76r:/dkMgl2Zul6zdkMgl2Zul6r
Size: 1048576 bytes
File type: EXE
Platform: WIN32
Entropy: Not Packed
PEID: UPolyXv05_v6
Company: no certificate found
Created at: 2007-09-10 17:57:50
Analyzed on: WindowsXP SP3 32-bit

Summary:

Worm. A program that is primarily replicating on networks or removable drives.

Payload

No specific payload has been found.

Process activity

The Worm creates the following process(es):

%original file name%.exe:412
at.exe:1652
at.exe:1308

The Worm injects its code into the following process(es):
No processes have been created.

File activity

The process %original file name%.exe:412 makes changes in the file system.
The Worm creates and/or writes to the following file(s):

%WinDir%\scvshosts.exe (7385 bytes)
%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\desktop.ini (67 bytes)
%WinDir%\hinhem.scr (7385 bytes)
%System%\scvshosts.exe (7385 bytes)
%System%\blastclnnn.exe (7385 bytes)
%System%\autorun.ini (181 bytes)

Registry activity

The process %original file name%.exe:412 makes changes in the system registry.
The Worm creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths]
"Directory" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path4]
"CacheLimit" = "65452"
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache4"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Connections]
"SavedLegacySettings" = "3C 00 00 00 17 00 00 00 01 00 00 00 00 00 00 00"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"AppData" = "%Documents and Settings%\%current user%\Application Data"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"GlobalUserOffline" = "0"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{c155cd73-744b-11e2-8294-806d6172696f}]
"BaseClass" = "Drive"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Cookies" = "%Documents and Settings%\%current user%\Cookies"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path2]
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache2"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Common AppData" = "%Documents and Settings%\All Users\Application Data"

[HKLM\System\CurrentControlSet\Services\Schedule]
"AtTaskMaxHours" = "0"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{c155cd75-744b-11e2-8294-806d6172696f}]
"BaseClass" = "Drive"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Cache" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files"

[HKLM\System\CurrentControlSet\Hardware Profiles\0001\Software\Microsoft\windows\CurrentVersion\Internet Settings]
"ProxyEnable" = "0"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path1]
"CacheLimit" = "65452"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer]
"NofolderOptions" = "1"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path2]
"CacheLimit" = "65452"

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "2A 55 5D 8A 76 DB AC 86 33 FE 18 6E 85 C0 BC 82"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path1]
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache1"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path3]
"CacheLimit" = "65452"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"MigrateProxy" = "1"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{c155cd72-744b-11e2-8294-806d6172696f}]
"BaseClass" = "Drive"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{b98117e8-75ca-11e2-81b2-000c293708fb}]
"BaseClass" = "Drive"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path3]
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache3"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths]
"Paths" = "4"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System]
"DisableRegistryTools" = "1"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"History" = "%Documents and Settings%\%current user%\Local Settings\History"

To automatically run itself each time Windows is booted, the Worm adds the following link to its file to the system registry autorun key:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
"Yahoo Messengger" = "%System%\scvshosts.exe"

The Worm modifies IE settings for security zones to map all local web-nodes with no dots which do not refer to any zone to the Intranet Zone:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"UNCAsIntranet" = "1"

The Worm modifies IE settings for security zones to map all web-nodes that bypassing proxy to the Intranet Zone:

"ProxyBypass" = "1"

Proxy settings are disabled:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"ProxyEnable" = "0"

The Worm modifies IE settings for security zones to map all urls to the Intranet Zone:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"IntranetName" = "1"

The Worm adds the reference to itself to be executed when a user logs on:

[HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon]
"Shell" = "Explorer.exe scvshosts.exe"

Task Manager is disabled:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System]
"DisableTaskMgr" = "1"

The Worm deletes the following value(s) in system registry:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"AutoConfigURL"
"ProxyServer"
"ProxyOverride"

The process at.exe:1652 makes changes in the system registry.
The Worm creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "67 73 DC 82 AE BF 5A D3 80 5B 4D 5D 3F 58 B5 65"

The process at.exe:1308 makes changes in the system registry.
The Worm creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "C8 66 BD 3A AE BC 9D 11 15 6A F2 CA E4 62 96 21"

Network activity (URLs)

URL	IP
hxxp://www.freewebs.com/setting3/setting.doc (ET CURRENT_EVENTS Possible Worm W32.Svich or Other Infection Request for setting.doc , Malicious)	75.98.17.24
hxxp://www.freewebs.com/setting3/setting.xls (ET CURRENT_EVENTS Possible Worm W32.Svich or Other Infection Request for setting.xls , Malicious)

HOSTS file anomalies

No changes have been detected.

Rootkit activity

No anomalies have been detected.

Propagation

Remove it with Ad-Aware

1. Click (here) to download and install Ad-Aware Free Antivirus.
2. Update the definition files.
3. Run a full scan of your computer.

Manual removal*

1. Terminate malicious process(es) (How to End a Process With the Task Manager):
   

   %original file name%.exe:412
   at.exe:1652
   at.exe:1308

2. Delete the original Worm file.
   
3. Delete or disinfect the following files created/modified by the Worm:
   

   %WinDir%\scvshosts.exe (7385 bytes)
   %Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\desktop.ini (67 bytes)
   %WinDir%\hinhem.scr (7385 bytes)
   %System%\scvshosts.exe (7385 bytes)
   %System%\blastclnnn.exe (7385 bytes)
   %System%\autorun.ini (181 bytes)

4. Delete the following value(s) in the autorun key (How to Work with System Registry):
   

   [HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
   "Yahoo Messengger" = "%System%\scvshosts.exe"

5. Remove the references to the Worm by modifying the following registry value(s) (How to Work with System Registry):
   

   [HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon]
   "Shell" = "Explorer.exe scvshosts.exe"

6. Clean the Temporary Internet Files folder, which may contain infected files (How to clean Temporary Internet Files folder).
   

*Manual removal may cause unexpected system behaviour and should be performed at your own risk.