Nemesis – Packet Injection Suite
Nemesis is a command-line network packet crafting and injection utility for UNIX-like and Windows systems. Nemesis, is well suited for testing Network Intrusion Detection Systems, firewalls, IP stacks and a variety of other tasks. As a command-line driven utility, Nemesis is perfect for automation and scripting.
Nemesis can natively craft and inject packets for:
- ARP
- DNS
- ETHERNET
- ICMP
- IGMP
- IP
- OSPF
- RIP
- TCP
- UDP
Using the IP and the Ethernet injection modes, almost any custom packet can be crafted and injected.
Unix-like systems require: libnet-1.0.2a, and a C compiler (GCC)
Windows systems require: libnetNT-1.0.2g and either WinPcap-2.3 or WinPcap-3.0
Download it here:
Source code: nemesis-1.4.tar.gz (Build 26)
Windows binary: nemesis-1.4.zip (Build 26) (includes LibnetNT)
You can read more here:
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In the title and tags should be Nemesis rather than Nemisis.
yzan: Thanks for the correction!
I’ve used Nemesis in the past, while teaching an IDS class. It’s a pretty good tool for creating arbitrary packets. I usually set up whatever header and payload the students need to detect, then just run it in a shell loop so it sends the same packets over and over. Works like a charm, and it’s pretty simple to get going.