WORM_PADOBOT.W

 Analysis by: Christopher Talampas

 ALIASES:

Backdoor:Win32/Berbew.BE (Microsoft), Win32/Spy.Qukart trojan (Eset), Net-Worm.Win32.Padobot (Ikarus)

 PLATFORM:

Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)

 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:

46,592 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

08 Apr 2009

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 and executes them:

  • %System%\{Random}32.exe

(Note: %System% is the Windows system folder, which is usually C:\Windows\System32.)

It drops the following files:

  • %System%\{Random3}32.dll
  • %System%\{Random4}32.dll
  • %System%\drivers\ndisrd.sys

(Note: %System% is the Windows system folder, which is usually C:\Windows\System32.)

It drops and executes the following files:

  • %System Root%\boot.sys
  • %System%\{Random2}.exe

(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.. %System% is the Windows system folder, which is usually C:\Windows\System32.)

Other System Modifications

This worm adds the following registry keys:

HKEY_CLASSES_ROOT\CLSID\{Random}

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\ndisrd

HKEY_CLASSES_ROOT\CLSID\{Random2}

HKEY_CLASSES_ROOT\CLSID\{Random3}

HKEY_LOCAL_MACHINE\SOFTWARE\Policies\
Microsoft\Windows\CurrentVersion

HKEY_CURRENT_USER\Software\Policies\
Microsoft\Windows

It adds the following registry entries:

HKEY_CLASSES_ROOT\CLSID\{Random}\
InProcServer32
(Default) = "%System%\{Random}.dll"

HKEY_CLASSES_ROOT\CLSID\{Random1}\
InProcServer32
ThreadingModel = "Apartment"

HKEY_CLASSES_ROOT\CLSID\{Random2}\
InProcServer32
(Default) = "%System%\{Random1}.dll"

HKEY_CLASSES_ROOT\CLSID\{Random3}\
InProcServer32
ThreadingModel = "Apartment"

HKEY_CLASSES_ROOT\CLSID\{Random4}\
InProcServer32
(Default) = "%System%\{Random2}.dll"

HKEY_CLASSES_ROOT\CLSID\{Random5}\
InProcServer32
ThreadingModel = "Apartment"

HKEY_CURRENT_USER\Software\Microsoft\
Windows
KKQHOOK = "28"

HKEY_CURRENT_USER\Software\Microsoft\
Windows
ifc = "0"

HKEY_CURRENT_USER\Software\Policies\
Microsoft\Windows\CurrentVersion\
Internet Settings\Zones\0
1601 = "0"

HKEY_CURRENT_USER\Software\Policies\
Microsoft\Windows\CurrentVersion\
Internet Settings\Zones\1
1601 = "0"

HKEY_CURRENT_USER\Software\Policies\
Microsoft\Windows\CurrentVersion\
Internet Settings\Zones\2
1601 = "0"

HKEY_CURRENT_USER\Software\Policies\
Microsoft\Windows\CurrentVersion\
Internet Settings\Zones\3
1601 = "0"

HKEY_CURRENT_USER\Software\Policies\
Microsoft\Windows\CurrentVersion\
Internet Settings\Zones\4
1601 = "0"

HKEY_LOCAL_MACHINE\SOFTWARE\Policies\
Microsoft\Windows\CurrentVersion\
Internet Settings\Zones\0
1601 = "0"

HKEY_LOCAL_MACHINE\SOFTWARE\Policies\
Microsoft\Windows\CurrentVersion\
Internet Settings\Zones\1
1601 = "0"

HKEY_LOCAL_MACHINE\SOFTWARE\Policies\
Microsoft\Windows\CurrentVersion\
Internet Settings\Zones\2
1601 = "0"

HKEY_LOCAL_MACHINE\SOFTWARE\Policies\
Microsoft\Windows\CurrentVersion\
Internet Settings\Zones\3
1601 = "0"

HKEY_LOCAL_MACHINE\SOFTWARE\Policies\
Microsoft\Windows\CurrentVersion\
Internet Settings\Zones\4
1601 = "0"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\ndisrd
Group = "Network"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\ndisrd
ErrorControl = "1"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\ndisrd
Start = "0"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\ndisrd
Type = "1"

It modifies the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\3
1601 = "0"

(Note: The default value data of the said registry entry is 1.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\4
1601 = "0"

(Note: The default value data of the said registry entry is 1.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\3
1601 = "0"

(Note: The default value data of the said registry entry is 1.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\4
1601 = "0"

(Note: The default value data of the said registry entry is 1.)

Other Details

This worm connects to the following possibly malicious URL:

  • http://{BLOCKED}inaltrash.ru/index.html?ifc=0
  • http://www.{BLOCKED}er.ru/redirect.php?id=765
  • http://s.{BLOCKED}m.ru/wgo
  • http://{BLOCKED}relsss.com/wres.php?ifc=0

  SOLUTION

Minimum Scan Engine:

9.300

VSAPI OPR PATTERN File:

5.883.00

VSAPI OPR PATTERN Date:

08 Apr 2009

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_CLASSES_ROOT\CLSID
    • {Random}
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
    • ndisrd
  • In HKEY_CLASSES_ROOT\CLSID
    • {Random2}
  • In HKEY_CLASSES_ROOT\CLSID
    • {Random3}
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows
    • CurrentVersion
  • In HKEY_CURRENT_USER\Software\Policies\Microsoft
    • Windows

Step 4

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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\3
    • From: 1601 = "0"
      To: 1601 = 1
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\4
    • From: 1601 = "0"
      To: 1601 = 1
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\3
    • From: 1601 = "0"
      To: 1601 = 1
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\4
    • From: 1601 = "0"
      To: 1601 = 1

Step 5

Search and delete these files

[ Learn More ]
There may be some files 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.
  • %System%\{Random3}32.dll
  • %System%\{Random4}32.dll
  • %System%\drivers\ndisrd.sys
  • %System Root%\boot.sys
  • %System%\{Random2}.exe

Step 6

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


Did this description help? Tell us how we did.