Network Intrusion Detection with Fragrouter

Published on July 18, 2020 1 min read

Fragrouter is a program for routing network traffic in such a way as to elude most network intrusion detection systems. Most attacks implemented correspond to those listed in the Secure Networks ”Insertion, Evasion, and Denial of Service: Eluding Network Intrusion Detection” paper of January 1998.

Table of Contents

  1. Install Fragrouter
  2. Options
  3. Usage Example
  4. Resources

Install Fragrouter

Run this command on your debian distro (kali, ubuntu, etc.):

# Debian distros
sudo apt-get install fragrouter


Run this command to see all available options:

fragrouter -h

The options:

Version 1.6
Usage: fragrouter [-i interface] [-p] [-g hop] [-G hopcount] ATTACK

 where ATTACK is one of the following:

 -B1: base-1: normal IP forwarding
 -F1: frag-1: ordered 8-byte IP fragments
 -F2: frag-2: ordered 24-byte IP fragments
 -F3: frag-3: ordered 8-byte IP fragments, one out of order
 -F4: frag-4: ordered 8-byte IP fragments, one duplicate
 -F5: frag-5: out of order 8-byte fragments, one duplicate
 -F6: frag-6: ordered 8-byte fragments, marked last frag first
 -F7: frag-7: ordered 16-byte fragments, fwd-overwriting
 -T1: tcp-1:  3-whs, bad TCP checksum FIN/RST, ordered 1-byte segments
 -T3: tcp-3:  3-whs, ordered 1-byte segments, one duplicate
 -T4: tcp-4:  3-whs, ordered 1-byte segments, one overwriting
 -T5: tcp-5:  3-whs, ordered 2-byte segments, fwd-overwriting
 -T7: tcp-7:  3-whs, ordered 1-byte segments, interleaved null segments
 -T8: tcp-8:  3-whs, ordered 1-byte segments, one out of order
 -T9: tcp-9:  3-whs, out of order 1-byte segments
 -C2: tcbc-2: 3-whs, ordered 1-byte segments, interleaved SYNs
 -C3: tcbc-3: ordered 1-byte null segments, 3-whs, ordered 1-byte segments
 -R1: tcbt-1: 3-whs, RST, 3-whs, ordered 1-byte segments
 -I2: ins-2:  3-whs, ordered 1-byte segments, bad TCP checksums
 -I3: ins-3:  3-whs, ordered 1-byte segments, no ACK set
 -M1: misc-1: Windows NT 4 SP2 -
 -M2: misc-2: Linux IP chains -

Usage Example

Using interface eth0 (-i eth0), send ordered 8-byte IP fragments (-F1):

sudo fragrouter -i eth0 -F1


This resouces may help you:

That’s it. Thanks you. 🙂

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Hey, I'm Md Obydullah. I build open-source projects and write on Laravel, Linux server, modern JavaScript and more on web development.