CVE-2026-27016

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.
Cross-site Scripting
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
5.4 MEDIUM
NETWORK
LOW
LOW
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
GitHub_MCNA
5.4 MEDIUM
NETWORK
LOW
LOW
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Affected Products (NVD)
VendorProductVersion
librenmslibrenms
24.10.0 ≤
𝑥
< 26.2.0
𝑥
= Vulnerable software versions
Common Weakness Enumeration
References
https://github.com/librenms/librenms/commit/3bea263e02441690c01dea7fa3fe6ffec94af335
https://github.com/librenms/librenms/pull/19040
https://github.com/librenms/librenms/releases/tag/26.2.0
https://github.com/librenms/librenms/security/advisories/GHSA-fqx6-693c-f55g