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Articles by HLE authors

• Other articles by Bri Hatch and James Lee

Vendor Mailing Lists

• Red Hat
• SuSE
• Slackware
• Debian
• Immunix
• Linux-Mandrake
• Turbolinux

Security Mailing Lists

• SecurityFocus lists
  Bugtraq, Incidents, Vuln-dev, Focus-Linux, SF-News and many more.
• LinuxSecurity.com
  Excellent weekly updates on Linux security.
• Firewalls
  Original Firewalls mailing list, unmoderated
• Firewall-Wizards
  Firewall mailing list, moderated by firewall guru Marcus Ranum.
• Sans
  Sans weekly and monthly newsletters
• Cert
  Cert Advisories
• SAFER
  Security Alert for Enterprise Resources

Security and Hacking Websites

• LinuxSecurity.com
  Linux security news and resources.
• SANS
  System Administration, Networking and Security Organization
• CERT
  Computer Emergency Response Team
• CIAC
  Computer Incident Advisory Capability
• Security Focus
  Extensive vulnerability database, Custom security articles, and Security Focus mailing lists
• Security Portal
  Portal to many security sites and articles.

• Neohapsis Archives
  Achives of many security and vendor lists
• Insecure.org
  Nmap, list archives, exploits, and other excellent reading

• Packet Factory
  Network and security tools galore
• Attrition.org
  News, crypto, downloads, and the hacked web page mirror.
• hack.co.za
  Exploit archives
• Rootshell
  Exploit archives
• Anticode
  Exploits

• Phrack Magazine
  Phrack Magazine and archives, a must read.
• 2600 The Hacker Quarterly
• L0pht Heavy Industries
  Now part of .
• Technotronic
  News, security archives, exploits, and more.
• Packetstorm
  Searchable and downloadable database of hacking tools, countermeasures and documents

Sniffers

• Tcpdump
  Tcpdump network sniffer
• Hunt
  Sniffer and man-in-the-middle hijacking tool
• Dsniff
  Many sophisticated sniffing components, including monkey-in-the-middle for SSH and SSL
• Sniffit
• Ethereal
• Karpski
• Gnusniff

Security, Investigative, and Testing Tools/Suites

• Nmap
  The best portscanning tool around
• Lsof
  List Open Files shows open files, sockets, pipes, and more.
• Snort
  Snort Intrusion Detection System

System Scanners

• COPS
  The Computer Oracle and Password System, system vulnerability scanner.
• Tiger
  TAMU's system vulnerability scanner

Network Scanners

• SATAN
  Satan, the first public network scanner
• SAINT
  Security Administrator's Integrated Network Tool -- An enhancement to Satan
• SARA
  Security Auditor's Research Assistant -- our favorite Satan spinoff

• Nessus
  client/server vulnerability scanner, updated continuously.
• Toneloc modem war dialer

File Integrity Tools

• Tripwire file integrity tool: commercial
• Tripwire: Open Source version
• AIDE
  Advanced Intrusion Detection Environment, a Tripwire-like file integrity tool.
• Nabou
  Scriptable and extensible file integrity tool.

Log Analysis Tools

• Swatch
  Simple Watchdog, perl log analysis tool.
• Logcheck
  A cron-style log analysis tool.
• Logsurfer
  An advanced dynamic log analysis tool.

Port Scan Detectors

• Scanlogd
  Solar Designer's advanced scan detection tool with raw socket support.
• Abacus Port Sentry
  Scan detection tool with route-dropping capabilities.
• Klaxon
• Courtney

Encryption

• PGP Freeware
  Pretty Good Privacy encryption software
• GnuPG
  Fully open source PGP by the GNU project

• OpenSSL
  OpenSSL (Secure Sockets Layer) libraries
• Stunnel
  SSL Tunneling software, used to encrypt arbitrary cleartext protocols.

• OpenSSH
  Secure replacements for the cleartext telnet, rlogin, rsh, rcp, and ftp protocols. Contains links to other SSH versions as well.
• SSH FAQ

Enforcing Strong Passwords

• Cracklib
• anlpasswd
• passwd+
• npasswd

• OPIE
  (One-time Passwords In Everything)
• PAM (Plugable Authentication Modules)

Cracking Passwords

• John The Ripper
  Solar Designer's Unix-password cracking software.
• Crack
  Alec Muffett's Crack, the Granddaddy of password crackers.
• Slurpie
• Viper

Password Cracking Dictonaries

• ftp.fu-berlin.de

Mail Servers

• Postfix
  Wietse Venema's answer to Sendmail
• Qmail
  Dan Bernstein's answer to Sendmail
• Sendmail: Freeware
• Sendmail: Commercial

Preventing Spam

• spam.abuse.net
  Fight Internet Spam
• MAPS (Mail Abuse Prevention System)
  Home of the RBL, DUL and more.
• RBL (Real Time Blackhole List)
• ORBS (Open Relay Behaviour-Modification System)

• Mutt
  The best damned mail reader around.

Web Servers and Dynamic Content

• NetCraft Webserver Survey

• Apache
• Thttpd web server
• Jigsaw
• AOL Server
• Bash-httpd
  Yes, you can write a webserver in shell...
• Awk-httpd
  As if a shell webserver wasn't enough...

• Mod perl
• PHP

• Whisker CGI Scanner
• cgisecurity.com

Linux Hardening Tools

• Immunix
  Tools for preventing buffer overflows.
• Bastille
  Linux hardening scripts.
• Openwall Kernel Patches
  Linux kernel security patches by Solar Designer.
• LIDS
  Linux Intrusion Detection System, kernel patch for extreemly advanced access controls.

Access Controls and Firewalls

• Firewalls and Internet Security, the Second Hundred (Internet) Years
• The history of firewalls

• Netfilter configuration for 2.4 kernels
• tcpserver
  Dan Bernstein's ucspi-tcp package, like inetd but done right.

Firewall Configuration Tools

• Web Firewall Configuration Tool
  Creates ipfwadm or ipchains rulesets
• Gfcc
  GTK+ Firewall Control Center
• Firewall Builder
  GUI firewall policy compiler
• MonMotha's IPTables Firewall
• Seawall Ipchains-based firewall configuration
  Supports various VPN tunnels as well
• PHPFwgen
  PHP based firewall rule generator
• Jfwadmin
  X11 Java frontend for ipchains
• GTK Firewall Configuration Tool
• Mason Automated firewall builder

Open Source Firewalls

• TIS Firewall Tool Kit
  The granddaddy of firewalls
• The Linux Router Project
  Firewall and more on a single Floppy
• SmoothWall
  -
• Floppyfw
  2.2 Kernel Firewall on a bootable floppy
• Sinus Firewall
  Firewall on a minimum 2.0 kernel distribution

Assorted Linux and Open Source links

• GNU
  Project
• The Cathedral and the Bazaar
  A watershed paper describing the virtues of Open Source programming
• The Halloween Document
  Leaked Microsoft papers describing the Microsoft strategy to defeat Open Source
• Slashdot
  News for nerds, stuff that matters
• Freshmeat
  Links to the lastest Open Source code of note
• Linux Capabilities