GHSA-28p7-f6h6-3jh3
GitHub Security Advisory
LibreNMS has a Reflected XSS ('Cross-site Scripting') in librenms/includes/html/pages/wireless.inc.php
Advisory Details
### Summary
A Reflected Cross-Site Scripting (XSS) vulnerability in the "metric" parameter of the "/wireless" and "/health" endpoints allows attackers to inject arbitrary JavaScript. This vulnerability results in the execution of malicious code when a user accesses the page with a malicious "metric" parameter, potentially compromising their session and allowing unauthorized actions.
### Details
The "/wireless" and "/health" endpoints are vulnerable to reflected XSS in the "metric" parameter. An attacker can inject the following XSS payload into the "metric" parameter:
```<script>constructor['constructor'](atob('Y29uZmlybShkb2N1bWVudC5kb21haW4p'))();<!---->```
When the page is loaded with this malicious parameter, the script executes immediately. The vulnerability occurs due to improper sanitization of the "metric" parameter in the following sinks:
https://github.com/librenms/librenms/blob/7f2ae971c4a565b0d7345fa78b4211409f96800a/includes/html/pages/wireless.inc.php#L82
https://github.com/librenms/librenms/blob/7f2ae971c4a565b0d7345fa78b4211409f96800a/includes/html/pages/health.inc.php#L114
### PoC
1. Inject the following payload into the "metric" parameter of the "/wireless" or "/health" endpoint:
```<script>constructor['constructor'](atob('Y29uZmlybShkb2N1bWVudC5kb21haW4p'))();<!---->```
2. Access the page with the injected payload.
3. Observe that the injected script executes upon loading the page.
Example URL: ```http://<your_url>/wireless/metric=%3Cscript%3Econstructor['constructor'](atob('Y29uZmlybShkb2N1bWVudC5kb21haW4p'))();%3C!----%3E```
Example Request:
```http
GET /wireless/metric=%3Cscript%3Econstructor[%27constructor%27](atob(%27Y29uZmlybShkb2N1bWVudC5kb21haW4p%27))();%3C!----%3E HTTP/1.1
Host: <your_host>
Cookie: <your cookies>
```
### Impact
This vulnerability allows attackers to execute arbitrary JavaScript in the context of a user’s session by crafting a malicious URL. The attack could lead to session hijacking, unauthorized actions, or further exploitation by injecting malicious scripts.
Affected Packages
Related CVEs
Key Information
Dataset
Data from GitHub Advisory Database. This information is provided for research and educational purposes.