One of the core and powerful features in ServiceNow is ACL (Access Control List) management. Multiple levels of ACL definitions for tables, records and fields might lead into confusing debugging of operations and visibility of certain application areas.
Things become easier by leveraging special debugging feature for ACLs.
It can be enabled by clicking on:
System Security -> Debugging -> Debug Security Rules
After enabling Security Rule Debugging there many little bug icons appear next to each ACL relevant object (i.e. fields). Clicking on them you get a list of all assigned ACLs and passing flag (true/false):
In the sample above we see that read permission for Number field has been passed, but write – not. As a consequence there is a disable number field.
Please refer to ServiceNow documentation for more information.
ServiceNow Release – Kingston