EXPLOIT QNAP NAS Hybrid Backup Remote Code Execution Vulnerability (CVE-2021-28809)
The specific flaw exists within the RTSS server, which listens on TCP port 8899 by default. The issue results from the lack of authentication prior to allowing alterations to the system configuration. An attacker can leverage this vulnerability to execute arbitrary code in the context of the Administrator.
Remote command execution
Update vendor's patch.
IPS Anomaly Group
IPS Rule Default Action