TROJ_SWISYN.AG


 ALIASES:

Trojan:Win32/Malagent (Microsoft); Generic.dx!xyf (McAfee); Trojan.Gen (Symantec); Trojan.Win32.Swisyn.adto, Trojan.Win32.Swisyn.adto (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); Trojan.Generic.3766077 (FSecure)

 PLATFORM:

Windows 2000, Windows, XP, Windows Server 2003

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:

  • 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

File Size:

114,688 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

29 Nov 2011

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.

Autostart Technique

This Trojan adds the following registry entries to enable its automatic execution at every system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
Winlogin = "%User Profile%\Application Data\Winlogon.exe"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Winlogin = "%User Profile%\Application Data\Winlogon.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\{9AE5FBBD-EDA1-A5BE-CE09-1E9FEC6FBE8F
StubPath = "%User Profile%\Application Data\Winlogon.exe"

HKEY_CURRENT_USER\Software\Microsoft\
Active Setup\Installed Components\{9AE5FBBD-EDA1-A5BE-CE09-1E9FEC6FBE8F
StubPath = "%User Profile%\Application Data\Winlogon.exe"

Other System Modifications

This Trojan adds the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
Explorer\run

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\{9AE5FBBD-EDA1-A5BE-CE09-1E9FEC6FBE8F

HKEY_CURRENT_USER\SOFTWARE\Microsoft\
Active Setup\Installed Components\{9AE5FBBD-EDA1-A5BE-CE09-1E9FEC6FBE8F

It adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
Explorer\run
Winlogin = "%User Profile%\Application Data\Winlogon.exe"

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%User Profile%\Application Data\Winlogon.exe = "%User Profile%\Application Data\Winlogon.exe:*:Enabled:Windows Messanger"

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%System Root%\\{malware file name}.exe = "%System Root%\{malware file name}.exe:*:enabled:windows messanger"

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine:

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

[ Learn More ]

Step 3

Delete this registry key

[ Learn More ]

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\policies\Explorer
    • run
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Active Setup\Installed Components
    • {9AE5FBBD-EDA1-A5BE-CE09-1E9FEC6FBE8F
  • In HKEY_CURRENT_USER\SOFTWARE\Microsoft\Active Setup\Installed Components
    • {9AE5FBBD-EDA1-A5BE-CE09-1E9FEC6FBE8F

Step 4

Delete this registry value

[ Learn More ]

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
    • Winlogin="%User Profile%\Application Data\Winlogon.exe"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • Winlogin="%User Profile%\Application Data\Winlogon.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Active Setup\Installed Components\{9AE5FBBD-EDA1-A5BE-CE09-1E9FEC6FBE8F
    • StubPath="%User Profile%\Application Data\Winlogon.exe"
  • In HKEY_CURRENT_USER\Software\Microsoft\Active Setup\Installed Components\{9AE5FBBD-EDA1-A5BE-CE09-1E9FEC6FBE8F
    • StubPath="%User Profile%\Application Data\Winlogon.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\Explorer\run
    • Winlogin="%User Profile%\Application Data\Winlogon.exe"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\AuthorizedApplications\List
    • %User Profile%\Application Data\Winlogon.exe="%User Profile%\Application Data\Winlogon.exe:*:Enabled:Windows Messanger"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\AuthorizedApplications\List
    • %System Root%\{malware file name}.exe="%System Root%\{malware file name}.exe:*:enabled:windows messanger"

Step 5

Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_SWISYN.AG. 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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