Free and Open-Source Software
Free and Open-Source Software (FOSS) is software that is Free Software and Open-Source Software. There is so much FOSS in the security domain that I believe this warrants its own wiki page.
A
AirCrack-NG - A complete suite of tools to assess WiFi network security
B
C
D
E
F
G
H
I
IPTables - The userspace command line program used to configure the Linux 2.4.x and later packet filtering rulesets
J
K
L
M
N
Nikto - A free command-line utility vulnerability scanner
NMap - A network discovery and security auditing port/host scanner
O
P
Q
R
S
Snort (Community Ruleset) - A free and open-source network intrusion detection system (NIDS) and an intrusion prevention system (IPS)
T
tcpdump - A powerful command-line packet analyzer
U
V
W
Wireshark - The world’s foremost, widely-used network protocol analyzer
X
Y
Z
Zed Attack Proxy - The world's most widely used web application scanner
