BKDR_MECKLOW.A

 Analysis by: JessaD

 ALIASES:

Backdoor:Win32/Mecklow.A (Microsoft)

 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

This backdoor initially queries certain registry entries to check if the system is running under a proxy server. Otherwise, without a proxy server, the malware will just keep on attempting to resolve the host names. It then uses the proxy server to access cetain URLs. Some of the data it sends to the URLs includes computer name, IP Address, and malware installation time.

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

  TECHNICAL DETAILS

File Size:

Varies

File Type:

PE

Memory Resident:

Yes

Initial Samples Received Date:

14 Jan 2011

Payload:

Connects to URLs/Ips, Steals information

Arrival Details

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

It may be dropped by other malware.

Backdoor Routine

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

  • http://{BLOCKED}e.{BLOCKED}y.com/AWS{random characters}.jsp?{random characters}
  • http://{BLOCKED}plus.{BLOCKED}h.info/AWS{random characters}.jsp?{random characters}
  • http://{BLOCKED}l.{BLOCKED}SRULE.NET/AWS{random characters}.jsp?{random characters}

Other Details

This backdoor does the following:

  • It initially queries the following registry entries to check if the system is running under a proxy server:

    HKCU\Software\Microsoft\Windows\
    CurrentVersion\Internet Settings\Proxy Enable

    HKCU\Software\Microsoft\Windows\
    CurrentVersion\Internet Settings\Proxy Server

  • Otherwise, without a proxy server the malware will just keep on attempting to resolve the following host names:
    • {BLOCKED}l.{BLOCKED}srule.net
    • {BLOCKED}plus.{BLOCKED}h.info
    • {BLOCKED}e.{BLOCKED}oy.com
  • It then uses the proxy server to access the URLs.
  • Below are some of the data it sends to the URLs:
    • Computer name
    • IP address
    • Malware installation time
    However, as of this writing, the said sites failed to issue a reply/command.

  SOLUTION

Minimum Scan Engine:

8.900

FIRST VSAPI PATTERN FILE:

7.768.10

FIRST VSAPI PATTERN DATE:

14 Jan 2011

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 terminate files detected as BKDR_MECKLOW.A

[ Learn More ]
  1. 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.
  2. 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_MECKLOW.A. 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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