What is CVE-2026-48549?

CVE-2026-48549 is a medium-severity vulnerability in Nagios Enterprises, Llc. Core, classified under Cross-Site Request Forgery (CSRF). CVSS score: 6.5/10. Published 2026-08-26.

How severe is CVE-2026-48549?

Medium severity. CVSS v3 base score is 6.5 out of 10.

CSRF in Nagios Enterprises, Llc. Core

CVE-2026-48549

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.

Vulnerability class: CSRF (Cross-Site Request Forgery)

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N.

Affected products

Weakness classification (CWE)

CWE-352 — Cross-Site Request Forgery (CSRF)

References

disclosure@vulncheck.com (vendor-advisory, patch)
disclosure@vulncheck.com (release-notes)
disclosure@vulncheck.com (third-party-advisory)

Frequently asked questions

What is CVE-2026-48549?: CVE-2026-48549 is a medium-severity vulnerability in Nagios Enterprises, Llc. Core, classified under Cross-Site Request Forgery (CSRF). CVSS score: 6.5/10. Published 2026-08-26.
How severe is CVE-2026-48549?: Medium severity. CVSS v3 base score is 6.5 out of 10.