Classification

Category :

Malware

Type :

-

Aliases :

Korgo.A, Worm.Win32.Padobot.b, Padobot

Summary

Korgo (aka Padobot) is a network worm written by the Russian Hangup Team virus group. It spreads throughout the Internet using a vulnerability in Microsoft Windows LSASS. A description of the vulnerability can be found in Microsoft Security Bulletin MS04-011: https://www.microsoft.com/technet/security/bulletin/MS04-011.mspx

Removal

Based on the settings of your F-Secure security product, it will either move the file to the quarantine where it cannot spread or cause harm, or remove it.

A False Positive is when a file is incorrectly detected as harmful, usually because its code or behavior resembles known harmful programs. A False Positive will usually be fixed in a subsequent database update without any action needed on your part. If you wish, you may also:

  • Check for the latest database updates

    First check if your F-Secure security program is using the latest updates, then try scanning the file again.

  • Submit a sample

    After checking, if you still believe the file is incorrectly detected, you can submit a sample of it for re-analysis.

    Note: If the file was moved to quarantine, you need to collect the file from quarantine before you can submit it.

  • Exclude a file from further scanning

    If you are certain that the file is safe and want to continue using it, you can exclude it from further scanning by the F-Secure security product.

    Note: You need administrative rights to change the settings.

Technical Details

The worm is written in C++ and is approximately 10KB in size, packed using UPX.

When launching, the worm copies itself to the Windows system directory under a random name, and registers this file in the system registry auto-run key:

  • [HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run] WinUpdate = %system%\name of file

It also creates a registry key

  • HKLM\SOFTWARE\Microsoft\Wireless Server = 1

It creates the mutexes "10", "u2" and "uterm5" to flag its presence in the system. The worm chooses the IP-addresses of random machines to infect and attack, similar to other worms which exploit the same LSASS vulnerability.

Once infected, a victim machine will display an error message that the LSASS service has failed. After this error message has been displayed, the computer may reboot.

The worm open TCP ports 113, 3067 and 2041 to receive commands.

It attempts to connect to several IRC servers to receive commands and transmit data.

  • moscow-advokat.ru
  • graz.at.eu.undernet.org
  • flanders.be.eu.undernet.org
  • caen.fr.eu.undernet.org
  • brussels.be.eu.undernet.org
  • los-angeles.ca.us.undernet.org
  • washington.dc.us.undernet.org
  • london.uk.eu.undernet.org
  • lia.zanet.net
  • gaspode.zanet.org.za
  • irc.kar.net