AppDynamics has fixed a security issue introduced in Web Server Agent v18.104.22.168.
This issue was identified in all Web Server Agent versions between v22.214.171.124 and v126.96.36.199.
In v188.8.131.52, 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 184.108.40.206, which contains the resolution for this issue.
If upgrading to 220.127.116.11 is not viable, pre-4.2.3 agent versions that are 4.2.x should be sufficient.