Analysis by: Karl Dominguez
 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

It runs certain commands that it receives remotely from a malicious user. Doing this puts the affected computer and information found on the coomputer at greater risk.

It gathers certain information on the affected computer.

This backdoor arrives as an attachment to email messages spammed by other malware/grayware/spyware or malicious users. It may be downloaded by other malware/grayware/spyware from remote sites. It may be unknowingly downloaded by a user while visiting malicious websites.

  TECHNICAL DETAILS

File Size: 235,008 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 12 Apr 2011
Payload: Compromises system security

Arrival Details

This backdoor arrives as an attachment to email messages spammed by other malware/grayware/spyware or malicious users.

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

It may be unknowingly downloaded by a user while visiting malicious websites.

NOTES:

Backdoor Routine

This backdoor executes the following command(s) from a remote malicious user:

  • Manipulate files
  • Create/delete directories
  • Create processes
  • Execute arbitrary cmd shell commands

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

  • {BLOCKED}nmlgb.3322.org
  • {BLOCKED}ns.8800.org
  • {BLOCKED}ef.2288.org

This malware opens a random port where it listens for commands from a remote user.

Information Theft

This backdoor gathers the following information on the affected computer:

  • Computer Name
  • Drive Information

The information is sent to the above-mentioned sites.

Other Details

It sets the attribute of itself to Hidden.

  SOLUTION

Minimum Scan Engine: 8.900
VSAPI OPR PATTERN File: 8.109.00
VSAPI OPR PATTERN Date: 21 Apr 2011

Step 1

For Windows ME and XP users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.

Step 2

Identify and terminate files detected as BKDR_MICRO.SMA

[ Learn More ]
  1. For Windows 98 and ME users, 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 3

Scan your computer with your Trend Micro product to delete files detected as BKDR_MICRO.SMA 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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