CVE-2020-36856

HIGH
Published Oct 30, 2025 Modified Nov 5, 2025 CWE-78

Description

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.

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CVSS v3.1 Score

8.8
HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-78 OS Command Injection

Affected Products

Vendor Product
nagios nagios_xi

References

Frequently Asked Questions

What is 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. It has a CVSS v3.1 base score of 8.8 (HIGH).
How severe is CVE-2020-36856? +
CVE-2020-36856 has a CVSS v3.1 score of 8.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.
What products are affected by CVE-2020-36856? +
CVE-2020-36856 affects products from nagios, specifically: nagios_xi. Check the affected products table above for specific version ranges.
How do I check if I'm vulnerable to CVE-2020-36856? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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