CVE-2026-48553: Nagios Enterprises, Llc Nagios Core

High severity, CVSS 7.5. EPSS: 1% chance of exploitation in the next 30 days.

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.

Affected products

Published 2026-08-12. Last modified 2026-09-08.