How severe is GHSA-6xmx-xr9p-58p7?

GHSA-6xmx-xr9p-58p7 has a CVSS score of 4.3/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-6xmx-xr9p-58p7?

GHSA-6xmx-xr9p-58p7 affects the following packages: librenms/librenms (Packagist). Ecosystems affected: Packagist.

How do I fix GHSA-6xmx-xr9p-58p7?

Update librenms/librenms to 26.2.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-6xmx-xr9p-58p7 is resolved across your whole dependency graph.

How do I detect GHSA-6xmx-xr9p-58p7 in my Packagist dependencies?

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.

How do I mitigate GHSA-6xmx-xr9p-58p7 if there is no patch (or I can't update yet)?

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 does O3 Security protect against GHSA-6xmx-xr9p-58p7?

O3 pinpoints whether GHSA-6xmx-xr9p-58p7 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is GHSA-6xmx-xr9p-58p7 actively exploited in the wild?

No public exploit code has been indexed for GHSA-6xmx-xr9p-58p7 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-6xmx-xr9p-58p7?

GHSA-6xmx-xr9p-58p7 has an EPSS (Exploit Prediction Scoring System) score of 0.2%, placing it in the 15th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is GHSA-6xmx-xr9p-58p7?

GHSA-6xmx-xr9p-58p7 is classified as Cross-site Scripting (XSS) (CWE-79). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was GHSA-6xmx-xr9p-58p7 published, and has it been updated?

GHSA-6xmx-xr9p-58p7 was published on February 18, 2026 and was last updated on February 20, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐘 Packagist

GHSA-6xmx-xr9p-58p7

MEDIUM

LibreNMS has a Stored XSS in Alert Rule

Also known asCVE-2026-26989

Published

Feb 18, 2026

Updated

Feb 20, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

EPSS Exploitation Probability

via FIRST.org ↗

0.2%probability of exploitation in next 30 days

Lower Risk15th percentile+0.24%

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

1 pkg affected

🐘librenms/librenms

Real-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 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:

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" />
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.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`librenms/librenms`	all versions	26.2.0

Detection & mitigation playbook

Open-source dependency

Detect
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 26.2.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-6xmx-xr9p-58p7 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-6xmx-xr9p-58p7 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-6xmx-xr9p-58p7. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### 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, t

O3 Security · Impact-Aware SCA

Is GHSA-6xmx-xr9p-58p7 in your dependencies?

O3 detects GHSA-6xmx-xr9p-58p7 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works

CVSS Score

4.3/10

CVSS v3 base score

Vector breakdown

AV:Attack Vector

Network

AC:Attack Complexity

Low

PR:Privileges Required

High

UI:User Interaction

Required

S:Scope

Unchanged

C:Confidentiality

Low

I:Integrity

Low

A:Availability

Low

Raw vector

CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:L/I:L/A:L

CWE Classification

CWE-79Cross-site Scripting (XSS)

Weaponization

No known public exploit tooling found.

OpenSSF Scorecard

Package health score

librenms

5.3/10

Maintained10/10

Code-Review7/10

Branch-Protection0/10

Assessed Jun 22, 2026

Timeline

Disclosed

Feb 18, 2026

Last updated

Feb 20, 2026

Identifiers

GHSA-6xmx-xr9p-58p7

References

Advisorynvd.nist.gov Webgithub.com Webgithub.com Webgithub.com Webgithub.com Packagegithub.com

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