hannoI contacted the responsible project, but I never got an answer and never really got to the bottom of this. But here's what I think happened: This was a proof of concept file for a yet unfixed and undisclosed vulnerability. It appears the developer already had a testcase for that bug in his local copy of the source tree. And then created the tarball from that source tree. And by doing that leaked a PoC for a zeroday. FWIW, it was "only" a DoS bug. But still.
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