The Metasploit Framework is the open source penetration testing framework with the world's largest database of public, tested exploits.

SecurityFocus is the most comprehensive and trusted source of security information on the Internet.

黑白前线是一个致力于打造国内最大的网络安全培训基地的团队，通过学习黑客知识，了解黑客入侵技术，才能更好地做好网络安全防御！

国内后起之秀以普及中国网络安全为贡献，我们提供了从基础到最前沿先进顶端技术的全方位优质服务，努力打造最好的安全网站。

发行黑客技术杂志，提供黑客技术指导、安全工具和技术讨论社区。

About Panda Security Founded in 1990, Panda Security is the world's leading provider of cloud-based security solutions, with products available in more than 23 languages and millions of users located in 195 countries around the world.

Windows and Linux anti virus, firewall, anti spam, recovery solutions against malware infection - Avira AntiVir.

道特韦伯（北京）信息技术有限公司，总部位于中国北京，在华北，华南地区均设立分支机构。公司位于中关村高新技术开发区-----上地硅谷亮城，是一家高起点，高技术，年轻而又充满活力的信息安全企业。

Download Antivirus software, Anti Spyware, firewall and Internet security tools for home users and businesses. Manage online threats with F-Secure antivirus and IT security solutions.

G Data Software AG is an innovative and rapidly expanding software house focusing on IT security solutions.