[aaronblohowiak]

If I implied that I doubted them, then I failed to communicate my point effectively -- I am very curious about how to turn a class allocate + instance_variable_set into remote code exec. I see how you can create the arel objects for sqli, but not arbitrary ruby.

[jgeralnik]

If you wait a couple of weeks you are much more likely to get an answer. Since all rails apps were vulnerable, most people who know how to execute arbitrary code are keeping silent for now.

[cmpb]

It's not a full-on answer, but it should clear up a little bit about how this vulnerability is possible.

http://www.insinuator.net/2013/01/rails-yaml/