CVE-2026-48550 json
Nagios Core / XI cmd.cgi Reflected XSS via NagFormId Parameter
published 2026-08-12 2 mo ago modified 2026-09-08 2 mo ago also EUVD-2026-57324
- cvss
- 6.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 38%
- public exploits
- 0
- none known
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.
Patch / fix
- Nagios Enterprises, LLC. Nagios Core 4.5.14
- Nagios Enterprises, LLC. Nagios XI 2026R1.7
- nagios4 Debian 12 4.4.6-4+deb12u2
- nagios4 Debian 13 4.4.6-4.1+deb13u2
- nagios4 Debian 14 4.5.14+ds-1
debian advisories DEBIAN-CVE-2026-48550
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2 mo ago
Exploit prediction
0.44% chance of exploitation in the next 30 days, higher than 38% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 5.1 | 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 |
| CNA | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| CNA | 4.0 | 5.1 | 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- Nagios Enterprises, LLC. Nagios Core
- Nagios Enterprises, LLC. Nagios XI
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
nagios.com
/security-disclosures/nagios-core/
vendor-advisory, patch
-
github.com
/NagiosEnterprises/nagioscore/blob/master/Changelog
release-notes
-
vulncheck.com
/advisories/nagios-core-xi-cmd-cgi-reflected-xss-via-nagformid-parameter
third-party-advisory
Sources
- CVE List CVE-2026-48550
- NVD CVE-2026-48550
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.