---
id: CVE-2026-45694
title: LibreNMS is a network monitoring system
summary: >-
  LibreNMS is a network monitoring system. In versions up to and including
  26.4.0, the Proxmox application view is vulnerable to reflected cross-site
  scripting through the user-supplied instance and vmid GET parameters, which
  are reflected…
severity: medium
cvss: 5.4
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N'
cwe:
  - CWE-79
vendor: librenms
product: librenms/librenms
affected:
  - librenms/librenms <= 26.4.0
patched:
  - librenms/librenms 26.5.0
published: '2026-08-26'
updated: '2026-09-09'
sourceUpdated: '2026-09-09T21:09:13.080'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-45694'
references:
  - url: >-
      https://github.com/librenms/librenms/commit/0be1bfd7746cea26bf7da40e82b70f75b724d0f8
    label: security-advisories@github.com
  - url: >-
      https://github.com/librenms/librenms/security/advisories/GHSA-jmqm-f8q4-v7wx
    label: security-advisories@github.com
  - url: 'https://github.com/librenms/librenms/releases/tag/26.5.0'
  - url: 'https://github.com/advisories/GHSA-jmqm-f8q4-v7wx'
tags:
  - nvd
  - ghsa
  - composer
epss: 0.00235
epssPercentile: 0.12805
aliases:
  - GHSA-jmqm-f8q4-v7wx
ecosystem: composer
ingestedAt: '2026-08-12T15:53:06.053Z'
---

## Overview

LibreNMS is a network monitoring system. In versions up to and including 26.4.0, the Proxmox application view is vulnerable to reflected cross-site scripting through the user-supplied instance and vmid GET parameters, which are reflected into the page title without adequate encoding. The parameters are placed into the page title with only strip_tags applied, and the title is then written into an inline document.title assignment through string interpolation, so a single quote terminates the JavaScript string and the remaining input runs as script. An attacker who lures an authenticated user into following a crafted link can execute script in that user's session, enabling actions such as theft of session data. This issue is fixed in version 26.5.0.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Package advisory (CVE-2026-45694)

Affected packages:

- `librenms/librenms <= 26.4.0`

Patched in:

- `librenms/librenms 26.5.0`

Source: https://github.com/advisories/GHSA-jmqm-f8q4-v7wx