Poster is a spyware.
Spyware can be installed either with or without users' consent, and either with or without their knowledge about the data gathered and/or the use of it.
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 uses stealth techniques to avoid being detected by the user:
- It injects itself in running processes.
Poster 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.