Introduction

We often run untrusted or complex applications on our systems.
Web browsers like opera or netscape.
Bind daemon for DNS.

Due to their nature, these applications may result in a security compromise.
Evil web pages may cause browser to send or delete files.
Bugs in an irc client can be used to install back doors.

Preventing or detecting such compromises is difficult.
New exploit tools available.
Evasion of Network IDS.