I am not sure why this is considered a security problem, so if you have some background on this assessment, we would be very interested in that.
However, there is a way to turn this off. This cookie is from our real user monitoring to understand usage patterns of Dynatrace. Under Settings on the Preference screen you have to disable the switch that says "Help us improve Dynatrace..." - once that is turned off, you should not see this cookie anymore for new sessions.
These cookies do not have any security or privacy relevant session information and just used for monitoring the performance of our product. We use real user monitoring for our own product and these cookies are part of it. The cookies are needed to identify which web requests belong to a user action.