Entry submission stucks forever if custom field contains ' for single quote

I’m using channel form module, so member can submit entries on my site. We’ve a wygwam field on the form, i’ve noticed wygwam converts single quote to

'

instantly. But once the form is submitted, the form stucks forever or timeout happen as security class fails for a preg_replace codes. My example input for the custom field -

Jon's code doesn't work

and it throws following error after submit - Fatal error: Maximum execution time of 90 seconds exceeded in /system/codeigniter/system/core/Security.php on line 389

It doesnt throws error if is submitted from backend.

Any urgent fix this?