LibreNMS before 26.3.1 Stored XSS via SNMP/Syslog Data

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.

Source published

1 Sep 2026 11:33:56 UTC

Source modified

8 Oct 2026 15:25:44 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

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CVSS 4.0 · 7.1 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N

CVSS 3.1 · 7.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N