Netsad.J is a worm that spreads by copying itself, without infecting other files.
It captures certain information entered or saved by the user, with the corresponding threat to privacy:
It sends the gathered information to a remote user by any available means: email, FTP, etc.
- In the local network:
it generates a large amount of network activity and consumes bandwidth.
It reduces the security level of the computer:
it terminates processes belonging to security tools, such as antivirus programs and firewalls, leaving the computer defenseless against attacks from other malware; it awaits remote-control orders received through
Netsad.J prevents access from programs to websites of several companies related with security tools (antivirus programs, firewalls, etc.).
It uses stealth techniques to avoid being detected by the user:
- It terminates processes corresponding to several security tools, such as antivirus programs and firewalls, to prevent detection.
Netsad.J uses the following propagation or distribution methods:
- Exploiting vulnerabilities with the intervention of the user: exploiting vulnerabilities in file formats or applications. To exploit them successfully it needs the intervention of the user: opening files, viewing malicious web pages, reading emails, etc.
- Via Internet, exploiting remote vulnerabilities: attacking random IP addresses, in which it tries to insert a copy of itself by exploiting one or more vulnerabilities.
- Peer-to-peer (P2P) file sharing programs: it makes copies of itself with enticing names in shared folders belonging to these programs. Other users of this type of networks then voluntarily download and run the infected files.