Moderate severityNVD Advisory· Published Feb 20, 2026· Updated Feb 20, 2026
LibreNMS has Stored XSS in Alert Rule
CVE-2026-26989
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.
Affected packages
Versions sourced from the GitHub Security Advisory.
| Package | Affected versions | Patched versions |
|---|---|---|
librenms/librenmsPackagist | < 26.2.0 | 26.2.0 |
Affected products
1Patches
1087608cf9f85Fix alert rule xss (#19039)
1 file changed · +2 −2
includes/html/modal/alert_rule_list.inc.php+2 −2 modified@@ -59,8 +59,8 @@ } echo " <tr> - <td>" . e(strip_tags((string)$rule['name'])) . "</td> - <td><i>" . e($rule_display) . "</i></td> + <td>" . e(strip_tags((string) $rule['name'])) . "</td> + <td><i>" . e(strip_tags((string) $rule_display)) . "</i></td> <td>{$rule['severity']}</td> <td>{$rule['id']}</td> </tr>
Vulnerability mechanics
Generated by null/stub on May 9, 2026. Inputs: CWE entries + fix-commit diffs from this CVE's patches. Citations validated against bundle.
References
6- github.com/advisories/GHSA-6xmx-xr9p-58p7ghsaADVISORY
- nvd.nist.gov/vuln/detail/CVE-2026-26989ghsaADVISORY
- github.com/librenms/librenms/commit/087608cf9f851189847cb8e8e5ad002e59170c58ghsax_refsource_MISCWEB
- github.com/librenms/librenms/pull/19039ghsax_refsource_MISCWEB
- github.com/librenms/librenms/releases/tag/26.2.0ghsax_refsource_MISCWEB
- github.com/librenms/librenms/security/advisories/GHSA-6xmx-xr9p-58p7ghsax_refsource_CONFIRMWEB
News mentions
0No linked articles in our index yet.