Bifrose.ZC 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:
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:
it converts the computer into a platform for taking malicious action surreptitiously: spam sending, launch of Denial of Service attacks, malware distribution, 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 changes the security settings of Internet Explorer, decreasing its security level; it awaits remote-control orders received through
Bifrose.ZC 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 injects itself in running processes.
- It deletes the original file from which it was run once it is installed on the computer.
It uses several methods in order to avoid detection by antivirus companies:
- It terminates its own execution if it detects that it is being executed in a virtual machine environment, such as VMWare or VirtualPC.
Bifrose.ZC 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.