Medium 6.1Published Aug 12, 2026

CVE-2026-48550Nagios Core / XI cmd.cgi Reflected XSS via NagFormId Parameter

Updated under an hour ago (Oct 26, 2026, 10:23 PM ET)

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It affects Nagios Enterprises, LLC. Nagios Core and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for Nagios Enterprises, LLC. Nagios Core

Exploited in the last 30 days

Nagios Core before 4.5.14 and Nagios XI before 2026R1.7 are vulnerable to reflected cross-site scripting in cmd.cgi via the NagFormId parameter. An unauthenticated remote attacker can craft a malicious link that, when followed by an authenticated user, executes arbitrary JavaScript in the victim's browser.

CVSS: 6.1 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Weakness (CWE): CWE-79
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: VulnCheck
NVD analysis: Awaiting Analysis
Record last updated: Aug 14, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Nagios Enterprises, LLC. Nagios Core nagios_enterprises:nagios_core (from the name)	before 4.5.14	CNA record
Nagios Enterprises, LLC. Nagios XI nagios_enterprises:nagios_xi (from the name)	before 2026R1.7	CNA record

References

References

https://www.nagios.com/security-disclosures/nagios-core/	vendor-advisory, patch
https://github.com/NagiosEnterprises/nagioscore/blob/master/Changelog	release-notes
https://www.vulncheck.com/advisories/nagios-core-xi-cmd-cgi-reflected-xss-via-nagformid-parameter	third-party-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.