cis is a forward-thinking nonprofit that harnesses the power of a global it community to safeguard public and private organizations against cyber threats.

nmap free security scanner, port scanner, & network exploration tool. download open source software for linux, windows, unix, freebsd, etc.

rankings and reviews of computer and network security software, programs, and tools.

the sans technology institute (sans.edu) offers career-focused undergraduate and graduate cyber security programs on the cutting edge of cybersecurity.

the exploit database - exploits, shellcode, 0days, remote exploits, local exploits, web apps, vulnerability reports, security articles, tutorials and more.

cvedetails.com is a vulnerability intelligence solution providing cve security vulnerability database, exploits, advisories, product and cve risk scores, attack surface intelligence, open source vulnerabilities, code changes, vulnerabilities affecting your attack surface and software inventory/tech stack. you can view cve vulnerability details, exploits, references, metasploit modules, full list of vulnerable products and cvss score reports and vulnerability trends over time

threatpost, is an independent news site which is a leading source of information about it and business security for hundreds of thousands of professionals worldwide.

wireshark: the world's most popular network protocol analyzer

nagios core is our original open-source monitoring solution, developed for and supported by hundreds of community members. create your ideal monitoring and

crowdstrike is a global cybersecurity leader with an advanced cloud-native platform for protecting endpoints, cloud workloads, identities and data.