This is a free, open source software that acts as a port scanner, security scanner and network exploration tool.
This fully automated scanner helps find any cybersecurity lapses in your digital space and explains the risks and their remedies.
Yet another open-source tool that can be downloaded for free, Metasploit Pro is a commercial product.
This provides a variety of tools to evaluate Wi-Fi network security. Aircrack Ng supports Windows, Linux, OpenBSD and other OS.
Wireshark supports cross-platform and performs deep inspection of different protocols.
OpenVAS is a fully-featured tool that can not only perform authenticated and unauthenticated testing but also performance tuning for large-scale scans.
This tool helps automate the process of detecting and exploiting SQL injection flaws and taking charge of database servers.
NetStumbler supports Windows OS and is a wireless networking tool that uses 802.11b, 802.11a, and 802.11g WLAN to detect wireless LANs.