Librenms has a reflected XSS on error alert

XSS on the parameters:/addhost -> param: community

of Librenms versions 24.10.1 (https://github.com/librenms/librenms) allows remote attackers to inject malicious scripts. When a user views or interacts with the page displaying the data, the malicious script executes immediately, leading to potential unauthorized actions or data exposure.

Proof of Concept:

1. Navigate to the /addhost path.

2. Fill in all required fields.

3. In the Community field, enter the following payload: "><img src=a onerror="alert(1)">.

4. Submit the form to save changes. 5 The script will execute when the error alert "No reply with community + payload" appears.

Impact:

Execution of Malicious Code