ALIASES:

Spammer:Win32/Tedroo.I (Microsoft); generic!bg.ftt (McAfee); Backdoor.DMSpammer (Symantec); Trojan-Proxy.Win32.Small.du (v) (Sunbelt); Trojan horse BackDoor.Agent.WXP (AVG)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • 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.

  TECHNICAL DETAILS

File Size: 34,304 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 23 May 2013

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.

Installation

This worm drops the following copies of itself into the affected system:

  • %Windows%\services.exe

(Note: %Windows% is the Windows folder, which is usually C:\Windows.)

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
services = "%Windows%\services.exe"

Other System Modifications

This worm deletes the following files:

  • °ýÞ
  • %Windows%\file.bat

(Note: %Windows% is the Windows folder, which is usually C:\Windows.)

It adds the following registry keys:

HKEY_LOCAL_MACHINE\Software\Policies\
Microsoft\WindowsFirewall\DomainProfile

HKEY_LOCAL_MACHINE\Software\Policies\
Microsoft\WindowsFirewall\StandardProfile

HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows\CurrentVersion\services

It adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Policies\
Microsoft\WindowsFirewall\DomainProfile
EnableFirewall = "0"

HKEY_LOCAL_MACHINE\SOFTWARE\Policies\
Microsoft\WindowsFirewall\StandardProfile
EnableFirewall = "0"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\services
del = "{malware path and file name}"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Desktop
id = "653148622056"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Desktop
host = "66.96.248.197"

It modifies the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Security Center
FirewallDisableNotify = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Security Center
FirewallOverride = "1"

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\SharedAccess
Start = "4"

(Note: The default value data of the said registry entry is 2.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\wscsvc
Start = "4"

(Note: The default value data of the said registry entry is 2.)

Dropping Routine

This worm drops the following files:

  • file.bat
  • %Windows%\services.exe

(Note: %Windows% is the Windows folder, which is usually C:\Windows.)

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine: 9.300

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

[ 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\Policies\Microsoft\WindowsFirewall
    • DomainProfile
  • In HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\WindowsFirewall
    • StandardProfile
  • In HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion
    • services

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
    • services = "%Windows%\services.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\WindowsFirewall\DomainProfile
    • EnableFirewall = "0"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\WindowsFirewall\StandardProfile
    • EnableFirewall = "0"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\services
    • del = "{malware path and file name}"
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Desktop
    • id = "653148622056"
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Desktop
    • host = "66.96.248.197"

Step 5

Restore these modified registry values

[ Learn More ]

Important:Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this only if you know how to or you can seek your system administrator's help. You may also check out this Microsoft article first before modifying your computer's registry.

  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Security Center
    • FirewallDisableNotify = "1"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Security Center
    • FirewallOverride = "1"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\SharedAccess
    • From: Start = "4"
      To: Start = ""2""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\wscsvc
    • From: Start = "4"
      To: Start = ""2""

Step 6

Search and delete these components

[ Learn More ]
There may be some components that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the "More advanced options" option to include all hidden files and folders in the search result.
  • file.bat
  • %Windows%\services.exe

Step 7

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

Step 8

Restore this file from backup only Microsoft-related files will be restored. If this malware/grayware also deleted files related to programs that are not from Microsoft, please reinstall those programs on you computer again.

  • °ýÞ
  • %Windows%\file.bat


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