My personal moment where Microsoft briefly showed me its true form:
Microsoft's Python language server extension for VS Code (Pylance) has been crashing on launch on one of my machines for twelve months or so.
One day, I got fed up with it and opened the extension in a JS debugger to investigate. Immediately after opening it, the extension fully deliberately DoSed [0] the CPU core with a full-on ReDoS [1] attack, leaving it spinning at 100% forever.