"A Russian security group has posted a detailed blog post about how they managed to extract the source code to over 3,300 websites. The group found that some of the largest and best known domains on the web, such as apache.org and php.net, amongst others, are vulnerable to an elementary information leak that exposes the structure and source of website files."

"The actual ‘exploit’ itself has been well known for a long time. It is the fault of the server administrator or developer, rather than the fault of a particular application, since the working metadata directories in Subversion are only required for working copies of code. What is surprising is just how prevalent the problem is – and who it affects. Finding version control metadata directories is as simple as looking for ‘.svn’ or ‘.cvs’ folders within web paths, for example: http://www.test.com/.svn/."

Read more: http://www.techcrunch.com/2009/09/23/basic-flaw-reveals-source-code-to-3300-popular-websites/