Yes, by now it should be clear that PowerShell is dangerous as hell, and if possible it should be blocked or at least monitored closely by HIPS/BB.
The Carbon Black report (PDF): https://www.carbonblack.com/wp-content/uploads/2016/04/Cb-Powershell-Deep-Dive-A-United-Threat-Research-Report-1.pdf
New Banking Trojan Uses PowerShell to Alter Internet Explorer Proxy Settings http://news.softpedia.com/news/new-...internet-explorer-proxy-settings-507538.shtml