Analysis by: Sammy Chua
ALIASES:

Troj/Dridex-KR (Sophos); Backdoor:Win32/Drixed.M (Microsoft); Trj/dridex.A (Panda)

 PLATFORM:

Windows

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

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel: Downloaded from the Internet, Dropped by other malware

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 connects to a website to send and receive information.

It modifies the Internet Explorer Zone Settings.

It steals certain information from the system and/or the user.

It deletes itself after execution.

  TECHNICAL DETAILS

File Size: 224,256 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 07 Dec 2015
Payload: Connects to URLs/IPs, Steals information

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.

Propagation

This backdoor does not have any propagation routine.

Backdoor Routine

This backdoor connects to the following websites to send and receive information:

  • {BLOCKED}.{BLOCKED}.113.105:243
  • {BLOCKED}.{BLOCKED}.35.56:8843
  • {BLOCKED}.{BLOCKED}.66.169:7447

As of this writing, the said sites are inaccessible.

Web Browser Home Page and Search Page Modification

This backdoor modifies the Internet Explorer Zone Settings.

Information Theft

This backdoor steals the following information:

  • Online banking/Social networking sites credentials
  • Browser screenshots

It gathers the following data:

  • Username
  • Computer name
  • Installation date
  • Installed programs and version

Other Details

This backdoor deletes itself after execution.

NOTES:

This backdoor may also perform the following:

  • Upload/Download and/or execute files
  • Monitor network traffic
  • Add infected host to botnet
  • Download updated configuration file
  • Download and execute modules (VNC)
  • Inject itself to web browsers (i.e. IE, Chrome, Firefox)

  SOLUTION

Minimum Scan Engine: 9.800
FIRST VSAPI PATTERN FILE: 12.196.06
FIRST VSAPI PATTERN DATE: 07 Dec 2015
VSAPI OPR PATTERN File: 12.197.00
VSAPI OPR PATTERN Date: 08 Dec 2015

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

Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.

Step 3

Restart in Safe Mode

[ Learn More ]

Step 4

Reset Internet security settings

[ Learn More ]

Step 5

Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_DRIDEX.YYSPK. 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 6

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