psad – Intrusion Detection and Log Analysis with iptables


psad is a collection of three lightweight system daemons (two main daemons and one helper daemon) that run on Linux machines and analyze iptables log messages to detect port scans and other suspicious traffic. A typical deployment is to run psad on the iptables firewall where it has the fastest access to log data.

psad incorporates many signatures from the Snort intrusion detection system to detect probes for various backdoor programs (e.g. EvilFTP, GirlFriend, SubSeven), DDoS tools (mstream, shaft), and advanced port scans (FIN, NULL, XMAS) which are easily leveraged against a machine via nmap.

When combined with fwsnort and the Netfilter string match extension, psad is capable of detecting many attacks described in the Snort rule set that involve application layer data. In addition, psad makes use of various packet header fields associated with TCP SYN packets to passively fingerprint remote operating systems (in a manner similar to p0f) from which scans originate.

For more information, see the complete list of features offered by psad.

psad is developed around three main principles:

  • Good network security starts with a properly configured firewall.
  • A significant amount of intrusion detection data can be gleaned from firewalls logs, especially if the logs provide information on nearly every field of the network and transport headers (and even application layer signature matches as in Netfilter’s case).
  • Suspicious traffic should not be detected at the expense of trying to also block such traffic.

You can download psad v2.1.4 here:

psad-2.1.4.tar.gz (Source tar)
psad-2.1.4-1.i386.rpm (i386 binary RPM).

Or read more here.

Posted in: Countermeasures, Networking Hacking, Security Software

, , , ,


Latest Posts:


dSploit APK Download - Hacking & Security Toolkit For Android dSploit APK Download – Hacking & Security Toolkit For Android
dSploit APK Download is a Hacking & Security Toolkit For Android which can conduct network analysis and penetration testing activities.
Scallion - GPU Based Onion Hash Generator Scallion – GPU Based Onion Hash Generator
Scallion is a GPU-driven Onion Hash Generator written in C#, it lets you create vanity GPG keys and .onion addresses (for Tor's hidden services).
WiFi-Dumper - Dump WiFi Profiles and Cleartext Passwords WiFi-Dumper – Dump WiFi Profiles and Cleartext Passwords
WiFi-Dumper is an open-source Python-based tool to dump WiFi profiles and cleartext passwords of the connected access points on a Windows machine.
truffleHog - Search Git for High Entropy Strings with Commit History truffleHog – Search Git for High Entropy Strings with Commit History
truffleHog is a Python-based tool to search Git for high entropy strings, digging deep into commit history and branches. This is effective at finding secrets accidentally committed.
AIEngine - AI-driven Network Intrusion Detection System AIEngine – AI-driven Network Intrusion Detection System
AIEngine is a next-generation interactive/programmable Python/Ruby/Java/Lua and Go AI-driven Network Intrusion Detection System engine with many capabilities.
Sooty - SOC Analyst All-In-One CLI Tool Sooty – SOC Analyst All-In-One CLI Tool
Sooty is a tool developed with the task of aiding a SOC analyst to automate parts of their workflow and speed up their process.


One Response to psad – Intrusion Detection and Log Analysis with iptables

  1. Goodpeople September 22, 2008 at 6:59 am #

    a lightweight ids.. good news for home users..