The AcroCEF or ReaderCEF is responsible for the communication with Adobe online services. In most cases the Acrobat application itself is not the problem, when it comes to high resource consumption of those two executibles. At first you should to connect a PC that has the problem you described to a hotspot without a proxy. Then, restart the Acrobat and see if this solves the problem. If so you have a problem inside your network. Check your proxy and WPAD.dat on any possible misconfigurations.