CVE-2026-48553: Improper Neutralization of Special Elements used in an OS Command

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...