ossec
OSSEC is an Open Source Host-based Intrusion Detection System. It performs log analysis, integrity checking, Windows registry monitoring, rootkit detection, real-time alerting and active response. It runs on most operating systems, including Linux, OpenBSD, FreeBSD, Mac OS X, Solaris and Windows
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Zed Attack Proxy (ZAP)
A penetration testing tool for finding vulnerabilities in web applications, from OWASP
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TeamPass
TeamPass is a Collaborative Passwords Manager. Its aim is to provide the ability to share password items through a secured and managed environment.
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testssl.sh
A command-line tool which checks a server's service on any port for the support of TLS/SSL ciphers, protocols as well as some cryptographic flaws. It's designed to provide clear output for your "is this good or bad" decision.
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Vaurien
A Chaos Monkey for TCP, it randomly disconnects or stalls TCP connections in your application to test application tolerance and high availability. Makes sure you correctly handle these unexpected events
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