CVE-2026-26989
LibreNMS has Stored XSS in Alert Rule
Description
LibreNMS is an auto-discovering PHP/MySQL/SNMP based network monitoring tool. Versions 25.12.0 and below are affected by a Stored Cross-Site Scripting (XSS) vulnerability in the Alert Rules workflow. An attacker with administrative privileges can inject malicious scripts that execute in the browser context of any user who accesses the Alert Rules page. This issue has been fixed in version 26.2.0.
INFO
Published Date :
Feb. 20, 2026, 2:16 a.m.
Last Modified :
Feb. 20, 2026, 4:25 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update LibreNMS to version 26.2.0 or later.
- Validate Alert Rules for malicious scripts.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-26989.
| URL | Resource |
|---|---|
| https://github.com/librenms/librenms/commit/087608cf9f851189847cb8e8e5ad002e59170c58 | Patch |
| https://github.com/librenms/librenms/pull/19039 | Issue Tracking |
| https://github.com/librenms/librenms/releases/tag/26.2.0 | Product Release Notes |
| https://github.com/librenms/librenms/security/advisories/GHSA-6xmx-xr9p-58p7 | Exploit Third Party Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-26989 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-26989
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-26989 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-26989 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Feb. 20, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N Added CPE Configuration OR *cpe:2.3:a:librenms:librenms:*:*:*:*:*:*:*:* versions up to (excluding) 26.2.0 Added Reference Type GitHub, Inc.: https://github.com/librenms/librenms/commit/087608cf9f851189847cb8e8e5ad002e59170c58 Types: Patch Added Reference Type GitHub, Inc.: https://github.com/librenms/librenms/pull/19039 Types: Issue Tracking Added Reference Type GitHub, Inc.: https://github.com/librenms/librenms/releases/tag/26.2.0 Types: Product, Release Notes Added Reference Type GitHub, Inc.: https://github.com/librenms/librenms/security/advisories/GHSA-6xmx-xr9p-58p7 Types: Exploit, Third Party Advisory -
New CVE Received by [email protected]
Feb. 20, 2026
Action Type Old Value New Value Added Description LibreNMS is an auto-discovering PHP/MySQL/SNMP based network monitoring tool. Versions 25.12.0 and below are affected by a Stored Cross-Site Scripting (XSS) vulnerability in the Alert Rules workflow. An attacker with administrative privileges can inject malicious scripts that execute in the browser context of any user who accesses the Alert Rules page. This issue has been fixed in version 26.2.0. Added CVSS V3.1 AV:N/AC:L/PR:H/UI:R/S:U/C:L/I:L/A:L Added CWE CWE-79 Added Reference https://github.com/librenms/librenms/commit/087608cf9f851189847cb8e8e5ad002e59170c58 Added Reference https://github.com/librenms/librenms/pull/19039 Added Reference https://github.com/librenms/librenms/releases/tag/26.2.0 Added Reference https://github.com/librenms/librenms/security/advisories/GHSA-6xmx-xr9p-58p7