This indicates an attack attempt to exploit a remote Code injection vulnerability in CryptoLOG.
The vulnerability is due to improper validation of user supplied inputs when handling a crafted HTTP request. A remote attacker may be able to exploit this to execute arbitrary command within the context of the process, via a crafted HTTP request.
CryptoLOG version 2015 and prior
System Compromise: Remote attackers can execute arbitrary commands within the context of the root user.
Currently we are unaware of any vendor supplied patch for this issue