Spybot.AHL is a backdoor that allows hackers to gain remote access to the affected computer in order to carry out actions that compromise user confidentiality and impede the tasks performed on the computer.
It captures certain information entered or saved by the user, with the corresponding threat to privacy:
passwords saved by certain Windows services; keystrokes, in order to obtain information for accessing online banking services, passwords and other confidential information.
It sends the gathered information to a remote user by any available means: email, FTP, etc.
It affects productivity, preventing tasks from being carried out:
- In the affected computer:
causes system slowdowns.
- In the local network:
it generates a large amount of network activity and consumes bandwidth.
It reduces the security level of the computer:
it listens on open ports in order to control the computer remotely; it awaits remote-control orders received through
Spybot.AHL 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 uses techniques included in its code to hide itself while it is active.
- It injects itself in running processes.
It uses several methods in order to avoid detection by antivirus companies:
- It prevents scanning tools from running, such as Windows Registry Editor, FileMonitor, etc.
- Its code is encrypted and it is only decrypted when it is going to run. Because of this, its code is not legible through a memory dump.
Spybot.AHL does not spread automatically using its own means. It needs an attacking user's intervention in order to reach the affected computer. The means of transmission used include, among others, floppy disks, CD-ROMs, email messages with attached files, Internet downloads, FTP, IRC channels, peer-to-peer (P2P) file sharing networks, etc.