Did you mean 4.2.2 or 4.2.3
Update to WP 4.2.3. was reported to break several plugins. This had to do with the change in the way shortcodes are handled. However, ACF was not one of those plugins as far as I know.
I have ACF installed on several sites running both 4.2.3 and 4.2.4 and I just tested on 4.2.2 and I’m not seeing any problems.
Have you tried deactivating other plugins on your site?
