Malware type: Worm

Aliases: Backdoor.Win32.EggDrop.v (Kaspersky), W32/Sdbot.worm.gen.t (McAfee), W32.Spybot.Worm (Symantec), HEUR/Crypted (Avira), W32/Rbot-Fam (Sophos), Backdoor:Win32/Rbot (Microsoft)

In the wild: Yes

Destructive: No

Language: English

Platform: Windows 95, 98, ME, NT, 2000, XP

Encrypted: No

Overall risk rating:

Reported infections:

Damage potential:


Distribution potential:



This worm takes advantage of the following Windows vulnerabilities:

  • IIS5/WEBDAV Buffer Overflow vulnerability
  • Remote Procedure Call (RPC) Distributed Component Object Model (DCOM) vulnerability
  • RPC Locator vulnerability
  • Windows LSASS vulnerability

For more information about these Windows vulnerabilities, please refer to the following Microsoft Web pages:

It also attempts to log on to systems using a list of user names and passwords. It drops a copy of itself into accessible machines.

This worm has backdoor capabilities. It executes commands sent in via Internet Relay Chat (IRC) and can be used to launch a Denial of Service (DoS) attack against specified target sites.

It terminates certain processes. It steals the CD keys of popular game applications.

This worm runs on Windows 95, 98, ME, NT, 2000, and XP.

For additional information about this threat, see:

Description created: Aug. 16, 2004 11:01:38 AM GMT -0800
Description updated: Aug. 16, 2004 3:36:53 PM GMT -0800


Size of malware: 292,934 Bytes (compressed)

Initial samples received on: Aug 16, 2004

Payload 1: Compromises system security

Trigger condition 1: Upon execution

Payload 2: Terminates processes

Trigger condition 1: Upon execution

Payload 3: Steals CD keys

Trigger condition 1: Upon execution

Installation and Autostart Technique

Upon execution, this worm drops a copy of itself as MS32CFG.EXE in the Windows system folder.

It then adds the following registry entries, which allow it to run automatically at every system startup:

Microsoft Features = "ms32cfg.exe"

Microsoft Features = "ms32cfg.exe"

Microsoft Features = "ms32cfg.exe"

Network Propagation and Exploits

This worm takes advantage of the Remote Procedure Call (RPC) Distributed Component Object Model (DCOM) vulnerability, which allows an attacker to gain full access and execute any code on a target machine.

Read more on this vulnerability from the following page:

This worm looks for vulnerable Windows XP machines on the network by scanning for random TCP/IP addresses on port 135.

It also exploits the RPC Locator vulnerability, which affects Windows NT-based systems. It searches for vulnerable WinNT machines on the network by incrementally scanning TCP/IP addresses on port 445.

More information on this vulnerability is available from the following Microsoft page:

It also exploits the IIS5/WEBDAV buffer overrun, which affects Windows NT-based systems and allows the execution of arbitrary codes. The following link offers more information from Microsoft about this vulnerability:

This worm also exploits the Windows LSASS vulnerability, which is a buffer overrun that allows remote code execution and enables an attacker to gain full control of affected systems. This vulnerability is discussed in detail in the following pages:

This worm copies and executes itself on vulnerable systems.

It searches for the following default network shares:

  • Admin$\System32
  • C$\WINNT\System32
  • C$\Windows\System32

It uses the default shares to determine access and copies itself to the shared folders if it has full access rights. However, if these shared folders have restricted access rights, it attempts to brute-force its way into the systems by logging on using the following user names and passwords:

Backdoor Capabilities

This worm has backdoor capabilities. It connects to the Internet Relay Chat (IRC) server as1.p1zd4t0.organd automatically joins the channel test, where it listens for commands coming from a remote user. It uses the nick teste3e3e. It executes commands locally on the affected machines, providing remote users virtual control over affected systems.

It acts as a bot that responds to private messages with specific keyword triggers. The following are the corresponding actions it performs:

  • Capture screen
  • Clone bot (the malware itself)
  • Delete files
  • Download file via FTP
  • Download files
  • Kill processes
  • Kill threads
  • List processes
  • List shares in system
  • List threads
  • Locate files on target system
  • Perform DDOS attack
  • Retrieve CD Keys
  • Retrieve network information
  • Scan for exploits
  • Send an email
  • Send files via the DCC IRC command
  • Start keylogging

Information Theft

This worm steals the CD keys of the following popular games:

  • Battlefield 1942
  • Battlefield 1942 (Road To Rome)
  • Battlefield 1942 (Secret Weapons of WWII)
  • Battlefield Vietnam
  • Black and White
  • Chrome
  • Command and Conquer: Generals
  • Command and Conquer: Generals (Zero Hour)
  • Command and Conquer: Red Alert
  • Command and Conquer: Red Alert 2
  • Command and Conquer: Tiberian Sun
  • Counter-Strike
  • FIFA 2002
  • FIFA 2003
  • Freedom Force
  • Global Operations
  • Gunman Chronicles
  • Half-Life
  • Hidden & Dangerous 2
  • IGI 2: Covert Strike
  • Industry Giant 2
  • James Bond 007: Nightfire
  • Legends of Might and Magic
  • Medal of Honor: Allied Assault
  • Medal of Honor: Allied Assault: Breakthrough
  • Medal of Honor: Allied Assault: Spearhead
  • Microsoft Windows
  • Nascar Racing 2002
  • Nascar Racing 2003
  • Need For Speed Hot Pursuit 2
  • Need For Speed: Underground
  • Neverwinter Nights
  • Neverwinter Nights (Hordes of the Underdark)
  • Neverwinter Nights (Shadows of Undrentide)
  • NHL 2002
  • NHL 2003
  • Rainbow Six III RavenShield
  • Shogun: Total War: Warlord Edition
  • Soldier of Fortune II - Double Helix
  • Soldiers Of Anarchy
  • The Gladiators
  • Unreal Tournament 2003
  • Unreal Tournament 2004

Process Termination

This worm terminates the following processes:

  • MSBLAST.exe
  • mscvb32.exe
  • mscvb32.exe
  • Penis32.exe
  • sysinfo.exe
  • sysinfo.exe
  • taskmon.exe
  • teekids.exe

It assumes that the above processes belong to other malware.

Denial of Service Attack

This worm allows remote users to launch the following types of flood attacks from infected machines against a target site:

  • PING flood
  • SYN flood
  • UDP flood

Other Details

This worm is compressed using either PE Compact or PeX and compiled using Microsoft Visual C%20%20.

Analysis by: Christine Bejerasco

Revision History:

First pattern file version: 2.282.02
First pattern file release date: Aug 16, 2004


Minimum scan engine version needed: 7.500

Pattern file needed: 3.490.02

Pattern release date: Jun 8, 2006

Important note: The "Minimum scan engine" refers to the earliest Trend Micro scan engine version guaranteed to detect this threat. However, Trend Micro strongly recommends that you update to the latest version in order to get comprehensive protection. Download the latest scan engine here.



To automatically remove this malware from your system, please refer to the Trend Micro Damage Cleanup Services.


Terminating the Malware Program

This procedure terminates the running malware process.

  1. Open Windows Task Manager.
    � On Windows 95, 98, and ME, press
    � On Windows NT, 2000, and XP, press
    CTRL%20SHIFT%20ESC, then click the Processes tab.
  2. In the list of running programs*, locate the process:
  3. Select the malware process, then press either the End Task or the End Process button, depending on the version of Windows on your system.
  4. To check if the malware process has been terminated, close Task Manager, and then open it again.
  5. Close Task Manager.

NOTE: On systems running Windows 95, 98, and ME, Windows Task Manager may not show certain processes. You can use a third party process viewer such as Process Explorer to terminate the malware process. Otherwise, continue with the next procedure, noting additional instructions.

Removing Autostart Entries from the Registry

Removing autostart entries from the registry prevents the malware from executing at startup.

  1. Open Registry Editor. Click Start>Run, type REGEDIT, then press Enter.
  2. In the left panel, double-click the following:
  3. In the right panel, locate and delete the entry:
    Microsoft Features = "ms32cfg.exe"
  4. In the left panel, double-click the following:
  5. In the right panel, locate and delete the entry:
    Microsoft Features = "ms32cfg.exe"
  6. In the left panel, double-click the following:
  7. In the right panel, locate and delete the entry:
    Microsoft Features = "ms32cfg.exe"
  8. Close Registry Editor.

NOTE: If you were not able to terminate the malware process as described in the previous procedure, restart your system.

Additional Windows ME/XP Cleaning Instructions

Running Trend Micro Antivirus

Scan your system with Trend Micro antivirus and delete all files detected as WORM_RBOT.HO. To do this, Trend Micro customers must download the latest pattern file and scan their system. Other users can use HouseCall, Trend Micro�s free online virus scanner.

Applying Patches

Download the latest patches. Information on the vulnerabilities exploited by this malware and corresponding patches can be found at the following links:

Microsoft Security Bulletin MS03-026
Microsoft Security Bulletin MS03-007
Microsoft Security Bulletin MS03-001
Microsoft Security Bulletin MS04-011

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