SecToolZ.com is a collection of free security tools used by security professionals and novice users.
Disassembler
OllyDbg
Hiew Hex Editor
IDA Pro disassembler
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Information Discovery
nmap
OWASP DirBuster
Network Sniffer
Wireshark
Tcpdump a well known Unix sniffer
Cain & Abel password recovery tool
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Password Cracker
John the Ripper password cracker
Cain & Abel password recovery tool
Ettercap - Silent Password Sniffer
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Port Scanner
nmap
Angry IP Scanner
Proxy
Echo Mirage Network Proxy
Odysseus Proxy Server
Fiddler is a Web Debugging Proxy
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Software Reverse Engineering
Hiew Hex Editor
IDA Pro disassembler
PatchDiff
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System Tools
Putty Windows SSH client
WinSCP Secure Download Software
WAF - Web Application Firewall
DotDefender Web Application Firewall