Analysis by: Christopher Daniel So
ALIASES:

Backdoor.Trojan (Symantec)

 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 may be dropped by other malware.

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

  TECHNICAL DETAILS

File Size: Varies
File Type: DLL
Memory Resident: Yes
Initial Samples Received Date: 18 Jan 2012
Payload: Connects to URLs/IPs

Arrival Details

This backdoor may be dropped by the following malware:

  • TROJ_JOBPAS.A
  • TROJ_JOBPAS.B

Backdoor Routine

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

  • 2 - Create a file
  • 3 - Open or execute a file
  • 4 - Enumerate processes
  • 5 - Open a remote Command Prompt
  • 8 - Uninstall this malware
  • 9 - Write to the file opened using command #2, then close the file

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

  • {BLOCKED}pdate.myfw.us:443

NOTES:

It connects to the following URL to check if it can connect to its C&C server:

    http://{BLOCKED}ababa.myfw.us/o.php

  SOLUTION

Minimum Scan Engine: 9.200
FIRST VSAPI PATTERN FILE: 8.716.03
FIRST VSAPI PATTERN DATE: 18 Jan 2012
VSAPI OPR PATTERN File: 8.717.00
VSAPI OPR PATTERN Date: 19 Jan 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

Remove malware/grayware files that dropped/downloaded BKDR_JOBPAS.A

Step 3

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

Step 4

Restart in Safe Mode

[ Learn More ]

Step 5

Search and delete the file detected as BKDR_JOBPAS.A

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden files in the search result.

Step 6

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


Did this description help? Tell us how we did.