AppDynamics has fixed a security issue introduced in Web Server Agent v188.8.131.52.
This issue was identified in all Web Server Agent versions between v184.108.40.206 and v220.127.116.11.
In v18.104.22.168, support for Virtual Hosts in Apache was added to the Web Server Agent. However, SSL connection requests between the Agent and Controller would fail when SSL was enabled within the Agent.
This issue did not impact any Web Servers Agents connected without SSL.
Customers with Web Server Agents that require SSL should connect to the controller and update to 22.214.171.124, which contains the resolution for this issue.
If upgrading to 126.96.36.199 is not viable, pre-4.2.3 agent versions that are 4.2.x should be sufficient.