zabbix_agentd in Zabbix before 1.8.6 and 1.9.x before 1.9.4 allows context-dependent attackers to cause a denial of service (CPU consumption) by executing the vfs.file.cksum command for a special device, as demonstrated by the /dev/urandom device.
https://support.zabbix.com/browse/ZBX-3794
https://exchange.xforce.ibmcloud.com/vulnerabilities/69378