The 2009 CWE/SANS Top 25 Most Dangerous Programming Errors is a list of the most significant programming errors that can lead to serious software vulnerabilities. They occur frequently, are often easy to find, and easy to exploit. They are dangerous because they will frequently allow attackers to completely take over the software, steal data, or prevent the software from working at all.
The list is the result of collaboration between the SANS Institute, MITRE, and many top software security experts in the US and Europe. It leverages experiences in the development of the SANS Top 20 attack vectors and MITRE's Common Weakness Enumeration (CWE). MITRE maintains the CWE web site, with the support of the US Department of Homeland Security's National Cyber Security Division, presenting detailed descriptions of the top 25 programming errors along with authoritative guidance for mitigating and avoiding them. The CWE site also contains data on more than 700 additional programming errors, design errors, and architecture errors that can lead to exploitable vulnerabilities.
The main goal for the Top 25 list is to stop vulnerabilities at the source by educating programmers on how to eliminate all-too-common mistakes before software is even shipped. The list will be a tool for education and awareness that will help programmers to prevent the kinds of vulnerabilities that plague the software industry. Software consumers could use the same list to help them to ask for more secure software. Finally, software managers and CIOs can use the Top 25 list as a measuring stick of progress in their efforts to secure their software.
http://cwe.mitre.org/top25/