Description: 

This memory-resident worm takes advantage of the following Windows vulnerabilities to propagate across networks:

• Remote Procedure Call (RPC) Distributed Component Object Model (DCOM) vulnerability
• IIS5/WEBDAV Bbuffer Overrun vulnerability
• LSASS vulnerability

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

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

It uses a list of user names and passwords to force its way into target machines and drops a copy of itself as SYSENTRY.EXE or SYSENTRY32.EXE in the Windows system folder.

This worm also has backdoor capabilities. It has a built-in Internet Relay Chat (IRC) client engine that connects to a specific IRC server. It then joins a particular channel, where it receives several malicious commands. It also steals CD keys of certain online game applications.

It is compressed using EXEStealth and runs on Windows 95, 98, ME, NT, 2000, and XP.

Details:

Installation and Autostart Techniques

Upon execution, this worm drops a copy of itself either as the file SYSENTRY.EXE or SYSENTRY32.EXE in the Windows system folder.

It creates the following registry entries to enable its automatic execution at every system startup:

HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows\CurrentVersion\RunServices
System Uptime Server = "<dropped_file>"

HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows\CurrentVersion\Run
System Uptime Server = "<dropped_file>"

HKEY_CURRENT_USER\Software\Microsoft\OLE
System Uptime Server = "<dropped_file>"

Network Propagation and Exploits

This worm also takes advantage of the following Windows vulnerabilities to facilitate its propagation:

• Remote Procedure Call (RPC) Distributed Component Object Model (DCOM) vulnerability
• IIS5/WEBDAV Bbuffer Overrun vulnerability
• LSASS vulnerability

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

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

It then drops a copy of itself on any vulnerable machines it finds.

It also searches for the following network shares:

• ADMIN$\System32
• C$\WINNT\System32
• C$\Windows\System32

If these folders have full access rights, this worm attempts to copy itself onto the said network shares. However, if the shared folders have restricted access rights, the worm attempts a force log on routine using a list of common user names and passwords.

Backdoor Capabilities

This worm has backdoor capabilities. It has a built-in Internet Relay Chat (IRC) client engine that connects to the IRC server dns2.nubela.net and then joins the channel #THEfourthDIMENSION.

It can perform the following tasks:

• Add registry autostart value and also a service with specified name
• Change IRC server
• Delete registry autostart value, service with specified name, and the original server file
• Disconnect/reconnect to the server
• Download a file from an FTP site
• Enable/disable shares, shell handler, and sniffer
• Execute an .EXE file and a command line function
• Execute a file from an FTP or a Web site
• Generate a new random nick
• Join/leave an IRC channel
• List all processes and services
• Load or save its configuration from a file
• Log on or off a current user
• Open a file
• Perform a mode change
• Send a file over DCC
• Send a private message through IRC
• Terminate itself and other processes
• Update the bot from a Web site
• Update itself from an FTP site

Information Theft

This worm is capable of gathering the Microsoft Windows Product ID, as well as the CD keys and serial numbers of the following software products, if installed on the affected system:

• 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 (Retail)
• 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
• 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

---

Analysis by: Glenn Lugod

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.

Solution:

AUTOMATIC REMOVAL INSTRUCTIONS

To automatically remove this malware from your system, please use Trend Micro Damage Cleanup Engine and Template.

MANUAL REMOVAL INSTRUCTIONS

Terminating the Malware Program

This procedure terminates the running malware process.

1. Open Windows Task Manager.
   On Windows 95, 98, and ME, press
   CTRL+ALT+DELETE
   On Windows NT, 2000, and XP, press
   CTRL+SHIFT+ESC, then click the Processes tab.
2. In the list of running programs*, locate any of the following processes:
   SYSENTRY.EXE
   SYSENTRY32.EXE
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:
   HKEY_LOCAL_MACHINE>Software>Microsoft>
   Windows>CurrentVersion>Run
3. In the right panel, locate and delete the entry:
   System Uptime Server = "<dropped_file>"
4. In the left panel, double-click the following:
   HKEY_LOCAL_MACHINE>Software>Microsoft>
   Windows>CurrentVersion>RunServices
5. In the right panel, locate and delete the entry:
   System Uptime Server = "<dropped_file>"
6. In the left panel, double-click the following:
   HKEY_CURRENT_USER>Software>Microsoft>OLE
7. In the right panel, locate and delete the entry:
   System Uptime Server = "<dropped_file>"
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

Users running Windows ME and XP must disable System Restore to allow full scanning of infected systems.

Users running other Windows versions can proceed with the succeeding procedure sets.

Running Trend Micro Antivirus

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

Applying Patches

This malware exploits known vulnerabilities in Windows. Download and install the fix patch supplied by Microsoft in the following pages:

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

Refrain from using this product until the appropriate patch has been installed. Trend Micro advises users to download critical patches upon release by vendors.

Trend Micro offers best-of-breed antivirus and content-security solutions for your corporate network, small and medium business, mobile device or home PC.