CVE-2020-36856Network attack vector

Authenticated command execution via unsanitized address

Published Oct 30, 2025 · Updated Oct 30, 2025

OS command injection in Nagios XI before 5.6.14 allows remote authenticated users to execute commands through the CCM web interface. The command_test.php handler incorporates the address parameter into backend shell commands without neutralizing shell metacharacters. CCM access is required; success runs commands as the web application account and can alter the underlying Linux host.

CVSS severity9.4
Critical
EPSS probability2.29%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

OS command injection in Nagios XI before 5.6.14 allows remote authenticated users to execute commands through the CCM web interface. The command_test.php handler incorporates the address parameter into backend shell commands without neutralizing shell metacharacters. CCM access is required; success runs commands as the web application account and can alter the underlying Linux host.

The record

CVE
CVE-2020-36856
Published
Oct 30, 2025
Updated
Oct 30, 2025
Vendor
Nagios Enterprises, LLC
Product
Nagios XI
Classifications
CWE-78, T1059.004, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 30, 2025CVE publishedPublication date reported by the CVE source.
  2. Oct 30, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <5.6.14

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Nagios Enterprises, LLC · Nagios XIversion=0 <5.6.14

Published CVSS scores

8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
9.4VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
T1059.004Command and Scripting Interpreter: Unix Shell
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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