CVE-2026-26992 LibreNMS has Stored Cross-Site Scripting via unsanitized /port-groups name
Attackers with admin privileges can inject malicious scripts via unsanitized port group names, leading to stored XSS attacks against other users.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-26992?
CVE-2026-26992 is a medium-severity cross-site scripting vulnerability in Librenms Librenms, published on 20 Feb 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
LibreNMS is an auto-discovering PHP/MySQL/SNMP based network monitoring tool. In versions 26.1.1 and below, the port group name is not sanitized, allowing attackers with admin privileges to perform Stored Cross-Site Scripting (XSS) attacks. When a user adds a port group, an HTTP POST request is sent to the Request-URI "/port-groups". The name of the newly created port group is stored in the value of the name parameter. After the port group is created, the entry is displayed along with relevant buttons such as Edit and Delete. This issue has been fixed in version 26.2.0.
Weakness: CWE-79
Which versions are affected by CVE-2026-26992?
2 open source packages ship an affected version, including librenms/librenms. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
librenms/librenms Packagist | All versions | 26.2.0 |
librenms/librenms Packagist | All versions | 26.2.0 |
Products include Librenms Librenms.
How do I fix CVE-2026-26992?
Upgrade librenms/librenms to 26.2.0 or later.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-26992 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-26992 exists.
Other vulnerabilities in Librenms Librenms
Sources
Also known as GHSA-93fx-g747-695x.