To clarify immediately, I'm not interested in writing a backdoor. I have no interest in submitting backdoor changelists to projects myself.

I'm researching some source modeling techniques, and we're interested in seeing if exploits or malicious code can be identified. We're using git and subversion histories to examine how a model snapshot captures relationships between the code. There is a question about whether certain types of code appear as outliers in an environment like this.

With that in mind, I'm having a hard time finding instances of a git/cvs/? open source repository with an example of a changelist that contained a backdoor, and was submitted and will show up in the logs.

We were looking at [proftpd as an early example](http://forums.proftpd.org/smf/index.php?topic=5206.0), but this exploit wasn't checked in but rather modified other versions of the code.

Are there examples in the revision history of an open source project of attempts to insert backdoor code?

Note: [I submitted this to StackOverflow a while ago](https://stackoverflow.com/questions/7679344/example-of-a-backdoor-submitted-to-an-open-source-project), but it was closed. I'm revisiting this now, and the recommendation was to ask here. Thanks!