RCE in Nagios Xi
CVE-2020-36856
Nagios XI versions prior to 5.6.14 contain an authenticated remote command execution vulnerability in the CCM command_test.php script. Insufficient validation of the `address` parameter allows an authenticated user with access to the Core Config Manager to inject shell metacharacters that are incorporated into backend command invocations. Successful exploitation enables arbitrary command execution with the privileges of the Nagios XI web application user and may be leveraged to execute commands on the underlying XI host, modify system configuration, or fully compromise the host.
Vulnerability class: Command Injection (OS Command Injection)
EPSS: 0.023 (81.4th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Nagios Nagios_xi
- Nagios Xi — versions 0
Weakness classification (CWE)
References
- disclosure@vulncheck.com (vendor-advisory, Release Notes, patch)
- disclosure@vulncheck.com (release-notes, Release Notes, patch)
- disclosure@vulncheck.com (Third Party Advisory, third-party-advisory)
Frequently asked questions
- What is CVE-2020-36856?
- CVE-2020-36856 is a high-severity vulnerability in Nagios Xi, classified under OS Command Injection. CVSS score: 8.8/10. Published 2025-10-30.
- How severe is CVE-2020-36856?
- High severity. CVSS v3 base score is 8.8 out of 10.