From the Red Hat CVE Database entry on CVE-2018-11776:
"Apache Struts versions 2.3 to 2.3.34 and 2.5 to 2.5.16 suffer from possible Remote Code Execution when using results with no namespace and in same time, its upper action(s) have no or wildcard namespace. Same possibility when using url tag which doesn't have value and action set and in same time, its upper action(s) have no or wildcard namespace."
Is CA Directory vulnerable to CVE-2018-11776?
Release: Component: ETRDIR
The simple answer is "No". CA Directory is not affected by CVE-2018-11776.