Console Password Manager (CPM)
Designed for System Administrators, to handle user logins for several computers running Linux. It works with a console interface, based on the CDK library that uses ncurses. Import data from csv files and export to text files with a free definable format.
Exploit World - Linux Section
Known vulnerabilities on the Linux system with detailed description.
Hacking Linux Exposed
Companion Website to Hacking Linux Exposed, Osborne/McGraw-Hill. Source code from the book, updates, and other tools to secure your Linux system.
This site on Linux and security covers firewalls (iptables), intrusion detection systems (snort), securing services, and Linux security in general. The aim is to provide information about protection, detection, and reaction with respect to attacks.
A kernel module that detects and stops overflow attacks, like Linux Buffer Overflow attack security, which aim to get an interactive access to the system.
SSH, the Secure Shell: The Definitive Guide
This is a companion website for "SSH: The Secure Shell The Definitive Guide" by Daniel Barrett and Richard Silverman (O'Reilly, 2003). It contains technical details on the SSH as well as sample book material.
Security-Enhanced Linux (SELinux)
National Security Agency research project, to modify the Linux kernel with enhanced security-related functions, including mandatory access controls. Now included in modern Linux kernels.
StegFS - A Steganographic File System for Linux
Not only does it encrypt data, it also hides it such that it cannot be proved to be there.