CVE-2026-48550 (GCVE-0-2026-48550)

Vulnerability from cvelistv5 – Published: 2026-08-12 16:30 – Updated: 2026-08-14 16:49
VLAI
Title
Nagios Core / XI cmd.cgi Reflected XSS via NagFormId Parameter
Summary
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.
Severity
5.1 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
6.1 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-12 18:14 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
Impacted products
Vendor Product Version CPE status
Nagios Enterprises, LLC. Nagios Core Affected: 0 , < 4.5.14 (semver)
guessed Create a notification for this product.
Nagios Enterprises, LLC. Nagios XI Affected: 0 , < 2026R1.7 (custom)
guessed Create a notification for this product.
Date Public
2026-08-05 00:00
Credits
Zach Hanley of Horizon3.ai
Show details on NVD website
To clipboard 

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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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