SSLsplit is a tool that performs man-in-the-middle attacks against SSL/TLS encrypted network connections for network forensics and penetration testing. It terminates SSL/TLS and initiates a new connection to the original destination, logging all data transmitted. It supports plain TCP and SSL, HTTP and HTTPS, and IPv4 and IPv6. For SSL and HTTPS, it generates and signs forged X509v3 certificates on-the-fly using the original certificate's subject DN and subjectAltName extension. It supports Server Name Indication, RSA, DSA, and ECDSA keys, and DHE and ECDHE cipher suites. It can also use existing certificates if the private key is available.
John the Ripper is a fast password cracker, currently available for many flavors of Unix, Windows, DOS, BeOS, and OpenVMS. Its primary purpose is to detect weak Unix passwords. It supports several crypt(3) password hash types commonly found on Unix systems, as well as Windows LM hashes. On top of this, lots of other hashes and ciphers are added in the community-enhanced version (-jumbo), and some are added in John the Ripper Pro.
Suricata is an Intrusion Detection and Prevention (IDS/IPS) engine developed by the Open Information Security Foundation and its supporting vendors. The engine is multi-threaded and has native IPv6 support, file extraction capabilities, and many more features. It's capable of loading existing Snort rules and signatures, and supports many frontends through Barnyard2.
aircrack-ng is a set of tools for auditing wireless networks. It's an enhanced/reborn version of aircrack. It consists of airodump (an 802.11 packet capture program), aireplay (an 802.11 packet injection program), aircrack (static WEP and WPA-PSK cracking), airdecap (decrypts WEP/WPA capture files), and some tools to handle capture files (merge, convert, etc.).
txtorcon is a Twisted-based asynchronous Tor control protocol implementation. Twisted is an event-driven networking engine written in Python, and Tor is an onion-routing network designed to improve people’s privacy and security on the Internet. It includes unit-tests with 96%+ coverage, multiple examples, and documentation. There are abstractions to track Tor configuration and state (circuits, streams), launch private instances, support Hidden Service, and more.
CERTivity is a powerful multi-platform visual tool for creating, managing, and handling different key store types (such as JKS, JCEKS, PKCS12, the Bouncy Castle types BKS and UBER, and Windows Native), public, private and secret keys in different formats (PKCS, OpenSSL, RSA/DSA, etc.), certificates (version 1 and 3), and certificates chains. It allows you to import and export keys, key pairs and certificates, manage certificate extensions, extend the validity period for self-signed certificates, test certificates, obtain revocation status, convert from one key store type to another, and much more.
strongSwan is a complete IPsec implementation for the Linux, Android, Maemo, FreeBSD, and Mac OS X operating systems. It interoperates with with most other IPsec-based VPN products via the IKEv2 or IKEv1 key exchange protocols. The focus of the strongSwan project is on strong authentication mechanisms using X.509 public key certificates and optional secure storage of private keys on smartcards through a standardized PKCS#11 interface. A rich choice of modular plugins adds additional features like Trusted Network Connect or advanced cryptographical algorithms.
Hiawatha is a secure and advanced Web server for Unix. It has been written with security as its main goal. It features advanced access control, prevention of SQL injection and cross-site scripting, banning of clients who try such exploits, the ability to run CGIs under any UID/GID you want, and many other features. These features make Hiawatha an interesting Web server for those who need more security than what the other available Web servers are offering. Hiawatha is also fast and easy to configure.