CVE-2026-48549

MEDIUM 6.5

Nagios Core / XI CSRF via cmd.cgi Double-Submit Cookie

CVSS Score

6.5

EPSS Score

0.0%

EPSS Percentile

0th

Nagios Core before 4.5.13 and Nagios XI before 2026R1.5 contains a CSRF vulnerability in cmd.cgi. When no Cookie header is present, the double-submit cookie protection can be bypassed by supplying matching NagFormId and nagFormId values in the POST body, allowing a cross-site request to execute Nagios commands as a currently authenticated user.

CWE	CWE-352
Vendor	nagios enterprises, llc.
Product	nagios core
Published	Aug 26, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

None

Integrity

High

Availability

None

Affected Versions

Nagios Enterprises, LLC. / Nagios Core

0 < 4.5.13

Nagios Enterprises, LLC. / Nagios XI

0 < 2026R1.5

References

NVD ↗ CVE.org ↗ EPSS Data ↗

nagios.com: https://www.nagios.com/security-disclosures/nagios-core/ github.com: https://github.com/NagiosEnterprises/nagioscore/blob/master/Changelog vulncheck.com: https://www.vulncheck.com/advisories/nagios-core-xi-csrf-via-cmd-cgi-double-submit-cookie

Credits

SeungMyung Lee