Analysis by: Roland Marco Dela Paz

ALIASES:

Troj/AutoIt-OU (Sophos)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel: Downloaded from the Internet, Dropped by other malware

This Trojan may be downloaded by other malware/grayware/spyware from remote sites. It may be dropped by other malware.

  TECHNICAL DETAILS

File Size: 470,939 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 26 Apr 2012
Payload: Modifies files

Arrival Details

This Trojan may be downloaded by other malware/grayware/spyware from remote sites.

It may be dropped by other malware.

It may be downloaded from the following remote sites:

  • {BLOCKED}.{BLOCKED}.196.130

Installation

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

  • %System%\gb_service.exe

(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)

It drops the following non-malicious file:

  • %System%\GB_CATCHME.EXE - a copy of GMER Catchme tool

(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)

Autostart Technique

This Trojan registers itself as a system service to ensure its automatic execution at every system startup by adding the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\AGBR5
ImagePath = "%System%\gb_service.exe"

NOTES:

This malware uninstalls a software called GbPlugin, a software that protects Brazilian bank customers when performing online banking transactions, from the affected system. It does the said routine by utilizing the GMER Catchme tool %System%\GB_CATCHME.EXE to delete GbPlugin related files and registries from a system. As a result, an infected user is left susceptible to banking malware that targets Brazilian banks.

(Note: %System% is the Windows system folder, which is usually C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)

  SOLUTION

Minimum Scan Engine: 9.200

Step 1

Scan your computer with your Trend Micro product to delete files detected as TROJ_KILSRV.EUIQ. 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 2

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 3

Restart in Safe Mode

[ Learn More ]

Step 4

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\SYSTEM\CurrentControlSet\Services
    • AGBR5

Step 5

Search and delete this file

[ Learn More ]
There may be some component 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%\GB_CATCHME.EXE

Step 6

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