CVE-2026-48553

Nagios Core before 4.5.13 and Nagios XI before 2026R1.5 are vulnerable to authenticated remote code execution via custom-variable macro injection through the Nagios Remote Data Processor (NRDP). When a custom variable defined on a host, service, or contact is referenced in a shell-executed command line, an authenticated attacker with NRDP access can inject OS commands through the macro value. Exploitation requires a non-default configuration in which a custom variable is defined and referenced in a shell-executed command.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.6 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/NagiosEnterprises/nagioscore/blob/master/Changelog
https://www.nagios.com/security-disclosures/nagios-core/
https://www.vulncheck.com/advisories/nagios-core-xi-authenticated-rce-via-custom-variable-macro-injection

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-12 17:17

Updated : 2026-09-08 20:28

NVD link : CVE-2026-48553

Mitre link : CVE-2026-48553

CVE.ORG link : CVE-2026-48553

JSON object : View

Products Affected

No product.

CWE

CWE-78

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

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