TSPY_AGENT.DAB


 ALIASES:

TrojanDownloader:Win32/Dibos.A, TrojanDownloader:Win32/Dibos.A (Microsoft); W32/Pinkslipbot.gen.aw (McAfee); Trojan.Gen (Symantec); Trojan.Win32.Regrun.jvx (Kaspersky); Trojan.Win32.EncPk.acl (v) (Sunbelt); Trojan.Generic.6996164 (FSecure)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

 OVERALL RISK RATING:
 REPORTED INFECTION:
 SYSTEM IMPACT RATING:
 INFORMATION EXPOSURE:

  • Threat Type: Spyware

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW


This spyware 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:

154,624 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

17 Jun 2012

Arrival Details

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

  • %User Profile%\firewall\system.exe

(Note: %User Profile% is the current user's profile folder, which is usually C:\Windows\Profiles\{user name} on Windows 98 and ME, C:\WINNT\Profiles\{user name} on Windows NT, and C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003.)

It creates the following folders:

  • %User Profile%\Application Data\firewall

(Note: %User Profile% is the current user's profile folder, which is usually C:\Windows\Profiles\{user name} on Windows 98 and ME, C:\WINNT\Profiles\{user name} on Windows NT, and C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003.)

Autostart Technique

This spyware modifies the following registry entries to ensure it automatic execution at every system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Winlogon
shell = "Explorer.exe %User Profile%\firewall\system.exe"

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

Other System Modifications

This spyware adds the following registry keys:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Applets\
Scandisk\data

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Applets\
Scandisk\hash\pi

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Applets\
Scandisk\data\pi

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Applets\
Scandisk\MRU

It adds the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Applets\
Scandisk\data
id = "{random values}"

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%User Profile%\firewall\system.exe = "%User Profile%\firewall\system.exe:*:Enabled:system.exe"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Applets\
Scandisk\hash\pi
0 = "2581b52c"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Applets\
Scandisk
counter = "1"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Applets\
Scandisk\data\pi
0~1 = "{random characters}"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Applets\
Scandisk\MRU
00 = "pi\0~1"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Applets\
Scandisk\MRU
!2 = "1"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Applets\
Scandisk\hash\pi
9 = "6cc81224"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Applets\
Scandisk
counter = "2"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Applets\
Scandisk\data\pi
9~2 = "{random characters}"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Applets\
Scandisk\MRU
01 = "pi\9~2"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Applets\
Scandisk\MRU
!2 = "2"

Other Details

This spyware connects to the following possibly malicious URL:

  • http://{BLOCKED}uffii.ru/dbs/logo90.php

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

Identify and delete files detected as TSPY_AGENT.DAB using either the Startup Disk or Recovery Console

[ 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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Applets\Scandisk
    • data
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Applets\Scandisk\hash
    • pi
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Applets\Scandisk\data
    • pi
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Applets\Scandisk
    • MRU

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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Applets\Scandisk\data
    • id = "{random values}"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\AuthorizedApplications\List
    • %User Profile%\firewall\system.exe = "%User Profile%\firewall\system.exe:*:Enabled:system.exe"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Applets\Scandisk\hash\pi
    • 0 = "2581b52c"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Applets\Scandisk
    • counter = "1"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Applets\Scandisk\data\pi
    • 0~1 = "{random characters}"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Applets\Scandisk\MRU
    • 00 = "pi\0~1"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Applets\Scandisk\MRU
    • !2 = "1"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Applets\Scandisk\hash\pi
    • 9 = "6cc81224"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Applets\Scandisk
    • counter = "2"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Applets\Scandisk\data\pi
    • 9~2 = "{random characters}"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Applets\Scandisk\MRU
    • 01 = "pi\9~2"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Applets\Scandisk\MRU
    • !2 = "2"

Step 5

Restore this modified 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 NT\CurrentVersion\Winlogon
    • From: shell = "Explorer.exe %User Profile%\firewall\system.exe"
      To: shell = ""Explorer.exe""

Step 6

Search and delete this folder

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.
  • %User Profile%\Application Data\firewall

Step 7

Scan your computer with your Trend Micro product to delete files detected as TSPY_AGENT.DAB. 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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