Virus Encyclopedia

Welcome to the Virus Encyclopedia of Panda Security.


Threat LevelModerate threat
DistributionNot widespread


Worms belonging to the Gaobot family have the following general effects:

  • They configure themselves: check their status, update themselves, uninstall themselves, etc.
  • They obtain information on the affected computer: CPU, RAM, disk space, operating system, etc.
  • They behave as sniffers, and spy on the network traffic.
  • They launch DDoS (distributed denial of service) attacks.
  • They send the worm to other IRC users.
  • They increase the network traffic on the ports 135 and 445

Additionally, some variants also carry out the following actions:

  • They search for specific text strings associated to several antivirus programs, firewalls, and system monitoring tools, in active processes. If any match is found, the process is ended, thus leaving the affected computer vulnerable to the attack of other viruses and worms.
  • They end the following processes if they are active:

    These processes belong to Nachi.A, Autorooter.A, Sobig.F and several variants of Blaster.
  • It prevents the user from visiting certain web sites, which mainly belong to several antivirus programs vendors.

Means of transmission 

Worms belonging to the Gaobot family spread across the Internet and networks.

1.- Transmission across the Internet.

It spreads by attacking IP addresses, in which it tries to exploit the LSASS, RPC DCOM and WebDAV vulnerabilities. However, although it contains code to exploit the vulnerability, it does not work properly.


2.- Transmission across networks.

It follows the routine below:

  • If the affected computer belongs to a network, it attempts to access the network shared resources C$, D$, E$, ADMIN$ and IPC$.
  • In order to do so, it uses passwords that are typical or easy to guess.
  • If successful, it makes copies of itself to the shared resources.


In addition, some Gaobot variants can take advantage of the ports opened in computers affected by the worms Bagle.A and Mydoom.A, in order to spread to these computers.

Further Details  

Gaobot.CJQ is written in the programming language Visual C++ v6.0.