A Brief Description and the Effect of Brontok.GS

It spreads and affects other computers. It executes actions that reduce the security level of the computer. It uses stealth techniques to avoid being detected by the user. It uses anti-monitoring techniques in order to prevent it being detected by antivirus companies. It spreads, through mapped drives, via shared network resources.
Brontok.GS is a worm that spreads by copying itself, without infecting other files.

It reduces the security level of the computer: it stops processes belonging to security tools, such as antivirus programs and firewalls, leaving the computer defenseless against attacks from other malware; it changes system permissions, reducing the security level.

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.
• It deletes the original file from which it was run once it is installed on the computer system.

It uses different methods in order to avoid detection by antivirus companies:
• It disallows scanning tools from running, such as Windows Registry Editor, FileMonitor, etc.

Brontok.GS 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.
• Computer networks (mapped drives): it generates copies of itself in mapped drives.
• Computer networks (shared resources): it creates copies of itself in shared network resources to which it has access.