Analysis by: Sabrina Lei Sioting

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

This Trojan is a malicious mIRC script that uses a legitimate mIRC client (daemon.exe) to connect to an IRC server and makes the affected computer a drone. Drones are hacked machines used to launch flood attacks.

It executes TROJ_BIRTTA.A files to hide/unhide files with specific file names (nicknames, main, users).

Once the system is connected to an IRC server, it will be able to do the following:

  • Flood a specified channel/IRC user

  • Flood server using port 6667

This malware uses two types of flooding attacks: the NICK flood and NOTICE flood. The NICK flood causes the channel window to be flooded with nickname changes notices by changing it rapidly. The NOTICE flood sends a lot of private messages to the victim. A private message opens a new message window and will urge the victim to close all of that windows easily by restarting the IRC client.

This Trojan arrives as a component bundled with malware/grayware packages. It may be dropped by other malware.

It connects to Internet Relay Chat (IRC) servers.

  TECHNICAL DETAILS

File Size: Varies
File Type: Script
Memory Resident: No
Initial Samples Received Date: 08 Jun 2011

Arrival Details

This Trojan arrives as a component bundled with malware/grayware packages.

It may be dropped by the following malware:

  • TROJ_DROPPR.FB

Backdoor Routine

This Trojan opens the following port(s) where it listens for remote commands:

  • 6667

It connects to any of the following Internet Relay Chat (IRC) servers:

  • Dream - {BLOCKED}rkbit.info
  • Dream - {BLOCKED}nd.com
  • Budapest - {BLOCKED}.182.255
  • Tampa - {BLOCKED}.20.130

It joins any of the following IRC channel(s):

  • #drones

NOTES:

This Trojan is a malicious mIRC script that uses a legitimate mIRC client (daemon.exe) to connect to an IRC server and makes the affected computer a drone. Drones are hacked machines used to launch flood attacks.

It executes TROJ_BIRTTA.A files to hide/unhide files with specific file names (nicknames, main, users).

Once the system is connected to an IRC server, it will be able to do the following:

  • Flood a specified channel/IRC user
  • Flood server using port 6667

This malware uses two types of flooding attacks: the NICK flood and NOTICE flood. The NICK flood causes the channel window to be flooded with nickname changes notices by changing it rapidly. The NOTICE flood sends a lot of private messages to the victim. A private message opens a new message window and will urge the victim to close all of that windows easily by restarting the IRC client.

  SOLUTION

Minimum Scan Engine: 8.900
FIRST VSAPI PATTERN FILE: 8.210.17
FIRST VSAPI PATTERN DATE: 09 Jun 2011
VSAPI OPR PATTERN File: 8.211.00
VSAPI OPR PATTERN Date: 09 Jun 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

Remove malware files dropped/downloaded by IRC_FLOODER.VI

Step 3

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

Related Malware