Washington-based open source group the Open Web Application Security Project (OWASP) has published a list of the most dangerous internet application security problems.

The group advises that governments and private sector organisations should take steps to protect themselves from these "surprisingly common" vulnerabilities.

Most attacks are well documented, but the group warned that major software development projects are still making the same mistakes.

OWASP's list includes:

Invalidated parameters Information from web requests is not validated before being used by a web application. Attackers can use these flaws to attack backside components through a web application.

Broken access control Restrictions on what authenticated users are allowed to do are not properly enforced.

Broken account and session management Account credentials and session tokens are not properly protected.

Cross-site scripting flaws The web application can be used as a mechanism to transport an attack to an end user's browser.

Buffer overflows Web application components in some languages that do not properly validate input can be crashed and, in some cases, used to take control of a process.

Command injection flaws Web applications pass parameters when they access external systems or the local operating system. If an attacker can embed malicious commands in these parameters the external system may execute them on behalf of the web application.

Error handling problems Error conditions that occur during normal operation are not handled properly.

Insecure use of cryptography Cryptography has proved difficult to code properly, which frequently results in weak protection.

Remote administration flaws If web-based administrative functions are not carefully protected an attacker can gain full access to all aspects of a site.

Web and application server misconfiguration Servers have many configuration options that affect security and are not secure out of the box.