This indicates an attack attempt to exploit an Remote Code Execution Vulnerability in Modx Revolution.
The vulnerability is due to an error in the vulnerable application when handling a maliciously crafted HTTP request. A remote attacker may be able to exploit this to execute arbitrary code within the context of the target application, via a crafted HTTP request.
Modx Revolution version 2.6.4 and prior
System Compromise: Remote attackers can gain control of vulnerable systems.
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