CVE-2026-48551

High

Description

Nagios Core before 4.5.14 and Nagios XI before 2026R1.7 contain a cross-site request forgery protection bypass via a self-supplied double-submit cookie. An attacker can supply matching cookie and request parameter values to bypass CSRF protection, enabling unauthenticated attackers to run commands as authorized users via malicious links.

SeverityHigh

CVSS7.4

Exploit probability—

ProductNagios Core

PublishedAug 12, 2026

First seenAug 12, 2026

Weakness typeCWE-352Cross-site request forgery (CSRF)

How to fix

Update

Nagios Enterprises, LLC. Nagios Core4.5.14 or later
Nagios Enterprises, LLC. Nagios XI2026R1.7 or later

Patches

nagios.com/security-disclosures/nagios-core/

Vendor advisories

github.com/NagiosEnterprises/nagioscore/blob/master/Changelog

Affected products

Product	Affected versions	Fixed in
Nagios Enterprises, LLC. Nagios Core	v < 4.5.14	4.5.14
Nagios Enterprises, LLC. Nagios XI	v < 2026R1.7	2026R1.7

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