The hidden-service feature in Tor before 0.3.0.8 allows a denial of service (assertion failure and daemon exit) in the connection_edge_process_relay_cell function via a BEGIN_DIR cell on a rendezvous circuit.
https://trac.torproject.org/projects/tor/ticket/22494
https://lists.torproject.org/pipermail/tor-announce/2017-June/000131.html
https://github.com/torproject/tor/commit/56a7c5bc15e0447203a491c1ee37de9939ad1dcd