This indicates an attack attempt to exploit an OS Command Injection vulnerability in Horde Project Groupware Webmail.
The vulnerability is due to insufficient sanitizing of user-supplied inputs in the application when handling a crafted HTTP Post request. A remote attacker may be able to exploit this to execute arbitrary code within the context of the application, via a crafted HTTP request.
Horde Groupware Webmail Edition 5.2.17
System Compromise: Remote attackers can gain control of vulnerable systems.
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