Exploit-db like websites, where people can search for security bugs

Question

If someone has to decide between 2 very similar server programs, or operating systems, then it searches on sites like:

http://www.exploit-db.com/search/

so that there he could get enough information about the given program/os's historical security bugs.

Do you know exploit-db like sites, where can people search for security bugs? What's the best place to search? What's the best place to compare two softwares/os-es?

Thank you!

Answer 1

Try these for a start:

http://www.securityfocus.com

http://osvdb.org

http://web.nvd.nist.gov

http://secunia.com

Answer 2

Couple others:

http://securityvulns.com/

http://www.vupen.com/english/security-advisories/

Answer 3

Let me cite:

www.cvedetails.com provides an easy to use web interface to CVE vulnerability data. You can browse for vendors, products and versions and view cve entries, vulnerabilities, related to them. You can view statistics about vendors, products and versions of products.