Description:
------------
I tried it with:
1) libssh2-1.5.0 - libssh2-1.8.0 
2) pecl-networking-ssh2-master (ver 1.0)

Test script:
---------------
<?php

$host = '***HOST***';
$port = '***PORT***';
$username = '***USERNAME***';
$password = '***PASS***';



$conn_id = ssh2_connect($host, $port);
if (!ssh2_auth_password($conn_id, $username, $password)) {
    echo "Invalid auth\n";
    exit;
}
echo "auth OK\n";

$stream = ssh2_exec($conn_id, "uname -a" . PHP_EOL);
if (!is_resource($stream)) {
    echo 'Invalid command'."\n";
    exit;
}
echo "exec OK\n";
stream_set_blocking($stream, true);
$response = stream_get_contents($stream);
echo "response OK\n";

Expected result:
----------------
auth OK
exec OK
response OK

Actual result:
--------------
auth OK
exec OK
Segmentation fault (core dumped)