| Attrition.org | | Attrition is an eclectic collection of internet and computer security resources. |
| Cult of the Dead Cow | | Offers blog, team background, tools and BackOrifice downloads, and news archive. |
| Eleventh Alliance | | Offers details regarding select viruses, overflow and security exploits, bios tools, and crytography. Also features book reviews on assembly programming and computer security. |
| enZo | | Coding group. Offer hacking tools and vulnerability exploits. |
| HackHull | | Group of hackers in the United Kingdom. Information about meetings, projects, and links to personal pages. |
| Nomad Mobile Research Centre | | Hacker lab engaged in vulnerabilities research. Security papers, full disclosure advisories and current projects. Also features a FAQ on hacking techniques. |
| Razor | | Team of security researchers. Features news, original papers and advisories, presentations they have given, and tools they have written. |
| Xfocus | | Organization dedicated to the research and demonstration of vulnerabilities in network services and communication security. Offers papers, security tools, exploit code, advisories and a discussion forum. | |
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