Vulnerability · Published Feb 20, 2026 · Assigned by GitHub_M

CVE-2026-27016LibreNMS has Stored XSS in Custom OID - unit parameter missing strip_tags()

Medium 5.4

In plain English

A medium-severity cross-site scripting in librenms from librenms. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 18% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)5.4Medium

Exploit odds (30 days)0.3%top 81.9% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

LibreNMS is an auto-discovering PHP/MySQL/SNMP based network monitoring tool. Versions 24.10.0 through 26.1.1 are vulnerable to Stored XSS via the unit parameter in Custom OID. The Custom OID functionality lacks strip_tags() sanitization while other fields (name, oid, datatype) are sanitized. The unsanitized value is stored in the database and rendered without HTML escaping. This issue is fixed in version 26.2.0.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Packagist	librenms/librenms	26.2.0	GHSA-fqx6-693c-f55g

Affected products (as reported)

Vendor	Product	Versions
librenms	librenms	>= 24.10.0, < 26.2.0

Weakness: CWE-79, CWE-116 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

References

https://github.com/librenms/librenms/security/advisories/GHSA-fqx6-693c-f55g x_refsource_CONFIRM
https://github.com/librenms/librenms/pull/19040 x_refsource_MISC
https://github.com/librenms/librenms/commit/3bea263e02441690c01dea7fa3fe6ffec94af335 x_refsource_MISC
https://github.com/librenms/librenms/releases/tag/26.2.0 x_refsource_MISC