We have identified and fixed a vulnerability caused by the way WebWorks/Struts and Freemarker templates are used in Bamboo.
The vulnerability allows a non-authenticated user to execute arbitrary Java methods in the JVM hosting the Bamboo application. This can be used to execute OS commands as the JVM user.
All versions of Bamboo up to and including 4.0.1 are affected.
Full details are available in the advisory at https://confluence.atlassian.com/display/BAMBOO/Bamboo+Security+Advisory+2012-08-28