High severity · published Sep 1, 2026
CVE-2026-84192
LibreNMS before 26.3.1 Stored XSS via SNMP/Syslog Data
7.1
CVSS
0.3%
EPSS
No
On KEV
Description
LibreNMS before 26.3.1 contains a stored cross-site scripting vulnerability in legacy PHP templates that output SNMP-sourced and syslog-sourced data without escaping. An attacker who controls a monitored network device can inject arbitrary JavaScript through SNMP interface descriptions or syslog program fields that executes when authenticated users view affected pages.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 26% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
librenms · librenms
before 26.3.1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-84192
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-84192
vendor-advisory
https://github.com/librenms/librenms/security/advisories/GHSA-7w8c-qgxg-m7jx
third-party-advisory
https://www.vulncheck.com/advisories/librenms-before-26.3.1-stored-xss-via-snmp-syslog-data
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