BKDR_LANOS.A

October 09, 2012
 Analysis by: Abraham Latimer Camba
 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

Infection Channel:

Dropped by other malware, Downloaded from the Internet

This backdoor arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It does not have any propagation routine.

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

It does not have any downloading capability.

It requires its main component to successfully perform its intended routine.

  TECHNICAL DETAILS

File Size:

12,800 bytes

File Type:

DLL

Memory Resident:

Yes

Initial Samples Received Date:

14 Jun 2012

Payload:

Steals information, Compromises system security

Arrival Details

This backdoor 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 backdoor drops the following non-malicious file:

  • %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.)

Propagation

This backdoor does not have any propagation routine.

Backdoor Routine

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

  • Download a file
  • Execute downloaded file
  • Get URL to download
  • Sleep for 5 seconds
  • Start a remote command prompt
  • Delete itself and exit

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

  • http://www.{BLOCKED}gadin47.com/a.asp?id={random characters}
  • http://www.{BLOCKED}gadin47.com/b.asp?id={random characters}
  • http://www.{BLOCKED}gadin47.com/c.asp?id={random characters}
  • http://www.{BLOCKED}gadin47.com/d.asp?id={random characters}
  • http://www.{BLOCKED}gadin47.com/e.asp?id={random characters}
  • http://www.{BLOCKED}gadin47.com/f.asp?id={random characters}
  • http://www.{BLOCKED}7.com/a.asp?id={random characters}
  • http://www.{BLOCKED}7.com/b.asp?id={random characters}
  • http://www.{BLOCKED}7.com/c.asp?id={random characters}
  • http://www.{BLOCKED}7.com/d.asp?id={random characters}
  • http://www.{BLOCKED}7.com/e.asp?id={random characters}
  • http://www.{BLOCKED}7.com/f.asp?id={random characters}

Download Routine

This backdoor does not have any downloading capability.

Information Theft

This backdoor gathers the following data:

  • Hostname
  • IP address
  • Operating system

Other Details

This backdoor requires its main component to successfully perform its intended routine.

NOTES:

It intercepts every API calls to the legitimate .DLL file, msacm32.dll. This routine allows it to execute every time the said .DLL file is loaded.

It sends the gathered information to the following URL:

  • http://{BLOCKED}.{BLOCKED}.202.198/qf.asp?id=flag:80nscqf host:{Hostname} IP:{IP address} OS:{Operating System} vm:{hex values} proxy:{hex values}

It saves the command it receives as %User Temp%\temp.ini.

It does not have rootkit capabilities.

It does not exploit any vulnerability.

  SOLUTION

Minimum Scan Engine:

9.200

FIRST VSAPI PATTERN FILE:

9.220.06

FIRST VSAPI PATTERN DATE:

28 Jun 2012

VSAPI OPR PATTERN File:

9.221.00

VSAPI OPR PATTERN Date:

28 Jun 2012

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

Scan your computer with your Trend Micro product and note files detected as BKDR_LANOS.A

Step 3

Restart in Safe Mode

[ Learn More ]

Step 4

Search and delete the file detected as BKDR_LANOS.A

*Note: Some component files may be 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.

To manually delete a malware/grayware file from the affected system:

  1. Right-click Start then click Search....
  2. In the Named input box, type the name of the file that was detected earlier.
  3. In the Look In drop-down list, select My Computer then press Enter.
  4. Once located, select the file then press SHIFT+DELETE to delete it.

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.
  • %User Temp%\temp.ini

Step 6

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

Step 7

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