CVE-2026-84191 json
LibreNMS before 26.5.0 Stored XSS via SNMP VRF fields
published 3mo ago modified 2mo ago also EUVD-2026-69028 , GHSA-g993-wffj-m3gv
Unreviewed: the maintainers' own advisory
Published by the maintainers on their GitHub repository librenms/librenms. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.
- cvss
- 6.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 18%
- public exploits
- 0
- none known
Summary
LibreNMS before 26.5.0 contains stored cross-site scripting vulnerabilities in VRF display pages where mplsVpnVrfDescription, vrf_name, and mplsVpnVrfRouteDistinguisher fields from SNMP polling are rendered without sanitization. Attackers controlling a monitored network device can inject arbitrary JavaScript through SNMP responses that executes in the browser of any user viewing VRF-related pages.
Patch / fix
- librenms librenms 26.5.0
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- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 2mo ago
Exploit prediction
0.26% chance of exploitation in the next 30 days, higher than 18% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/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 | 5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/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
- librenms librenms
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/librenms/librenms/security/advisories/GHSA-g993-wffj-m3gv
vendor-advisory, advisory
-
vulncheck.com
/advisories/librenms-before-26.5.0-stored-xss-via-snmp-vrf-fields
third-party-advisory
Sources
- CVE List CVE-2026-84191
- NVD CVE-2026-84191
- Maintainer advisory GHSA-g993-wffj-m3gv
Fencer Intel 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.
The maintainers of librenms/librenms published their own advisory on GitHub. Reviewed sources take precedence over it.