ghsa-vxq6-8cwm-wj99
Vulnerability from github
Summary
A stored Cross-Site Scripting (XSS) vulnerability exists in LibreNMS (<= 25.6.0) in the Alert Template creation feature. This allows a user with the admin role to inject malicious JavaScript, which will be executed when the template is rendered, potentially compromising other admin accounts.
Details
In the LibreNMS web UI, when a user with the admin role visits /templates and clicks "Create new alert template", the "Template name" field fails to properly sanitize input. By inserting a payload like:
<script>alert(document.cookie)</script>
and filling the other fields with arbitrary content (e.g., test), once the template is saved, the script is executed. This confirms that user input is stored and later rendered without proper output encoding.
This vulnerability can be exploited for session hijacking, data theft, or other malicious actions targeting other admin users.
PoC
- Log in to LibreNMS using an account with the admin role.
- Navigate to:
http://localhost:8000/templates. - Click the "Create new alert template" button.
- Input the following into the Template name field:
<script>alert(document.cookie)</script>
5. Fill the remaining fields (Template, Alert title, Recovery title) with arbitrary content such as test.
6. Click "Create template".
7. Upon saving, a JavaScript alert pops up, confirming the stored XSS is triggered.
Impact
Type: Stored Cross-Site Scripting (XSS)
Affected users: Only accounts with the admin role who access the Alert Templates page (http://localhost:8000/templates) are affected.
Attackers need: Authenticated admin-level access.
{
"affected": [
{
"package": {
"ecosystem": "Packagist",
"name": "librenms/librenms"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "25.8.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2025-55296"
],
"database_specific": {
"cwe_ids": [
"CWE-79"
],
"github_reviewed": true,
"github_reviewed_at": "2025-08-18T22:25:29Z",
"nvd_published_at": "2025-08-18T18:15:39Z",
"severity": "MODERATE"
},
"details": "### Summary\n\nA stored Cross-Site Scripting (XSS) vulnerability exists in LibreNMS (\u003c= 25.6.0) in the Alert Template creation feature. This allows a user with the **admin role** to inject malicious JavaScript, which will be executed when the template is rendered, potentially compromising other admin accounts.\n\n---\n### Details\n\nIn the LibreNMS web UI, when a user with the **admin role** visits `/templates` and clicks **\"Create new alert template\"**, the **\"Template name\"** field fails to properly sanitize input. By inserting a payload like:\n\n```\n\u0026lt;script\u003ealert(document.cookie)\u0026lt;/script\u003e \n```\n\nand filling the other fields with arbitrary content (e.g., `test`), once the template is saved, the script is executed. This confirms that user input is stored and later rendered without proper output encoding.\n\nThis vulnerability can be exploited for session hijacking, data theft, or other malicious actions targeting other admin users.\n\n---\n### PoC\n\n1. Log in to LibreNMS using an account with the **admin role**.\n2. Navigate to: `http://localhost:8000/templates`.\n3. Click the **\"Create new alert template\"** button.\n4. Input the following into the **Template name** field:\n\n ```\n \u0026lt;script\u003ealert(document.cookie)\u0026lt;/script\u003e\n ```\n5. Fill the remaining fields (`Template`, `Alert title`, `Recovery title`) with arbitrary content such as `test`.\n6. Click **\"Create template\"**.\n7. Upon saving, a JavaScript alert pops up, confirming the stored XSS is triggered.\n\u003cimg width=\"1574\" height=\"848\" alt=\"image\" src=\"https://github.com/user-attachments/assets/bc482874-c47e-48e3-83b6-cb4a9dcf4a53\" /\u003e\n\n---\n### Impact\n\n **Type**: Stored Cross-Site Scripting (XSS)\n **Affected users**: Only accounts with the **admin role** who access the Alert Templates page (`http://localhost:8000/templates`) are affected.\n **Attackers need**: Authenticated admin-level access.",
"id": "GHSA-vxq6-8cwm-wj99",
"modified": "2025-08-18T22:25:29Z",
"published": "2025-08-18T22:25:29Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/librenms/librenms/security/advisories/GHSA-vxq6-8cwm-wj99"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-55296"
},
{
"type": "WEB",
"url": "https://github.com/librenms/librenms/commit/8ade3d827d317f5ac4b336617aafff865f825958"
},
{
"type": "PACKAGE",
"url": "https://github.com/librenms/librenms"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:N",
"type": "CVSS_V3"
}
],
"summary": "LibreNMS allows stored XSS in Alert Template name field"
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.