Mikrotik RouterOs stable 6.47 suffers from a memory corruption vulnerability in the /nova/bin/diskd process. An authenticated remote attacker can cause a Denial of Service due to invalid memory access.
http://seclists.org/fulldisclosure/2021/May/23
http://packetstormsecurity.com/files/162533/MikroTik-RouterOS-Memory-Corruption.html