This indicates an attack attempt to exploit a remote Command Execution vulnerability in Apache Continuum.
The vulnerability is due to insufficient validation of user supplied inputs in the application. A remote attacker may be able to exploit this to execute arbitrary command under the security context of the target process, via a crafted request.
Apache Continuum 1.4.2 and prior version
System Compromise: Remote attackers can gain control of vulnerable systems.
Currently we are unaware of any vendor supplied patch for this issue