Cyber Posture

CVE-2020-36867

HighPublic PoC

Published: 30 October 2025

Published
30 October 2025
Modified
05 November 2025
KEV Added
Patch
CVSS Score 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0121 79.1th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Description

Adversaries may abuse Unix shell commands and scripts for execution.

Security Summary

CVE-2020-36867 is a command injection vulnerability (CWE-78) affecting Nagios XI versions prior to 5.7.3. The issue resides in the report PDF download/export functionality, where user-supplied values passed to the PDF generation pipeline or the wrapper invoking offline/pdf helper utilities are insufficiently validated or improperly escaped. This allows injection of shell metacharacters or arguments. The vulnerability has a CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).

An authenticated attacker with the ability to trigger PDF exports can exploit this vulnerability remotely over the network with low complexity and no user interaction required. Successful exploitation enables arbitrary command execution on the underlying system, potentially granting high-impact access to confidentiality, integrity, and availability.

Mitigation is addressed in the Nagios XI changelog at https://www.nagios.com/changelog/nagios-xi/, which details fixes in version 5.7.3 and later. Additional details on the vulnerability and remediation are available in the Vulncheck advisory at https://www.vulncheck.com/advisories/nagios-xi-command-injection-in-report-pdf-download.

Details

CWE(s)
CWE-78

Affected Products

nagios
nagios xi
≤ 5.7.3

MITRE ATT&CK Enterprise Techniques

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
Why these techniques?

CVE enables remote exploitation of a public-facing web application (Nagios XI) via authenticated command injection, directly facilitating T1190 and arbitrary Unix shell command execution (T1059.004).

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

References