BKDR_PROXY.HI

 Analysis by: Jaime Benigno Reyes

 ALIASES:

Troj/DwnLdr-KMT (Sophos), Trojan-Downloader.Win32.Agent (Sunbelt), Gen:Variant.Graftor.51804 (Bitdefender)

 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: Backdoor

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Dropped by other malware

This backdoor may be dropped by other malware.

It does not have any propagation routine.

It executes commands from a remote malicious user, effectively compromising the affected system.

It does not drop any other file.

As of this writing, the said sites are inaccessible.

  TECHNICAL DETAILS

File Size:

15,360 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

23 Jan 2013

Payload:

Compromises system security, Collects system information, Connects to URLs/IPs, Downloads files

Arrival Details

This backdoor may be dropped by the following malware:

  • TROJ_MDROPR.HI

Propagation

This backdoor does not have any propagation routine.

Backdoor Routine

This backdoor executes the following commands from a remote malicious user:

  • Execute files
  • Perform remote shell
  • Sleep for a specified amount of time
  • Download files
  • Delete self

It connects to the following URL(s) to send and receive commands from a remote malicious user:

  • http://{BLOCKED}.{BLOCKED}.233.241/grc/index.asp?id=flag:418xls%20host:{Host Name}%20IP:{IP Address}%20OS:{OS Version}%20vm:{special character}%20proxy:{special character}

Dropping Routine

This backdoor does not drop any other file.

Download Routine

This backdoor accesses the following websites to download files:

  • http://{BLOCKED}.{BLOCKED}.233.241/a.asp?id={random value}
  • http://{BLOCKED}.{BLOCKED}.233.241/b.asp?id={random value}

It saves the files it downloads using the following names:

  • %User Temp%\temp.ini

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.)

As of this writing, the said sites are inaccessible.

Information Theft

This backdoor gathers the following data:

  • Host Name
  • Local IP Address
  • OS Version

NOTES:

This backdoor does not have rootkit capabilities.

It does not exploit any vulnerability.

  SOLUTION

Minimum Scan Engine:

9.300

FIRST VSAPI PATTERN FILE:

9.678.05

FIRST VSAPI PATTERN DATE:

24 Jan 2013

VSAPI OPR PATTERN File:

9.679.00

VSAPI OPR PATTERN Date:

25 Jan 2013

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

Remove the malware/grayware file that dropped/downloaded BKDR_PROXY.HI

Step 3

Identify and terminate files detected as BKDR_PROXY.HI

[ Learn More ]
  1. Windows Task Manager may not display all running processes. In this case, please use a third-party process viewer, preferably Process Explorer, to terminate the malware/grayware/spyware file. You may download the said tool here.
  2. If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
  3. If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.

Step 4

Search and delete this file

[ 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.
  • %User Temp%\temp.ini

Step 5

Scan your computer with your Trend Micro product to delete files detected as BKDR_PROXY.HI. 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.

Related Malware