WordPress Plugin Advanced Custom Fields (ACF) is prone to a vulnerability that lets attackers upload arbitrary files because the application fails to properly verify user-supplied input. An attacker can exploit this vulnerability to upload arbitrary code and run it in the context of the webserver process. This may facilitate unauthorized access or privilege escalation; other attacks are also possible. WordPress Plugin Advanced Custom Fields (ACF) versions 5.0 - 5.12.2 are vulnerable.
Update to plugin version 5.12.3 or latest