Description:
------------
When using the output of bin2hex(random_bytes) in a openssl_seal, segaults starts occurring.

We got around this problem in our source by prepending an 'A' to the random bytes before calling bin2hex on them.

Crashed on all versions supporting random_bytes:
https://3v4l.org/lrLgW


Test script:
---------------
<?php
define(
    'KEY',
    <<<'KEY'
-----BEGIN PUBLIC KEY-----
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAqvjCLfpS0MyilIjR+IsH
HPH8TqFUCw4kTAVmTy9SDZV9hHYY2EPgrlTd7gvMP/DWipvBD6Y5w2bPdAQoXr5D
qEKAGkE+1El4hS8XyuOdYXSYTDH1HPSlFiGdgsnlkFcbh/fJyzIKBaGLnWxsjhiS
deiI7KuEkI9zt+X2r4KqFt/dhnXz0kcB1M7qyhQ6Rvijgjy/A1LsN4ZAREFLCEjb
1AP9nk0QAUHWcG5MvbgsE20Pn4R5wFsMFBTvNmb34jHFREgR9j4DYcV5FFR3tKb8
3XtjE9/kjfK29BSpiyXZs8PSqDhO00vh6txUB4VfkVUD2Bi93rxDeyALnCW7My+l
YwIDAQAB
-----END PUBLIC KEY-----
KEY
);

$bytes = random_bytes(32);
$iv    = '';

for ($i = 0; $i < 100; $i++) {
    openssl_seal(bin2hex($bytes), $sealed_data, $env_keys, [KEY], 'AES256', $iv);
    \ob_end_clean();
}

Expected result:
----------------
no output and no crash

Actual result:
--------------
Notice: P ��� in /in/lrLgW on line 22

Process exited with code 139.