I’ve seen this same thing on x86 RouterOS (although it did handle more traffic than your CCR). I believe this is Linux kernel related. No reason the router should blow up but it does. I didn’t have specific RAW rules in place so maybe in my case with more CPU available I’ll get it to a reasonable point.
I’m planning to do more thorough testing, just need to find the time. Unless someone out there can save me the effort and break it down for us? 