VDB-347062 · CVE-2026-27016 · GHSA-fqx6-693c-f55g

LibreNMS up to 26.1.x Custom OID strip_tags unit cross site scripting

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4.4	$0-$5k	0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in LibreNMS up to 26.1.x. Affected by this issue is the function strip_tags of the component Custom OID. Executing a manipulation of the argument unit can lead to cross site scripting. This vulnerability is tracked as CVE-2026-27016. The attack can be launched remotely. No exploit exists. You should upgrade the affected component.

Detailsinfo

A vulnerability has been found in LibreNMS up to 26.1.x and classified as problematic. This vulnerability affects the function strip_tags of the component Custom OID. The manipulation of the argument unit with an unknown input leads to a cross site scripting vulnerability. The CWE definition for the vulnerability is CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. As an impact it is known to affect integrity. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability was named CVE-2026-27016 since 02/17/2026. The exploitation appears to be easy. The attack can be initiated remotely. Successful exploitation requires user interaction by the victim. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1059.007 by the MITRE ATT&CK project.

Upgrading to version 26.2.0 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch 3bea263e02441690c01dea7fa3fe6ffec94af335 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

Name

LibreNMS

Version

License

open-source

Website

Product: https://github.com/librenms/librenms/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.4
VulDB Meta Temp Score: 4.4

VulDB Base Score: 3.5
VulDB Temp Score: 3.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.4
CNA Vector (GitHub_M): 🔒

CVSSv2info

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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Cross site scripting
CWE: CWE-79 / CWE-94 / CWE-74
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: LibreNMS 26.2.0
Patch: 3bea263e02441690c01dea7fa3fe6ffec94af335

Timelineinfo

02/17/2026 CVE reserved
02/20/2026 +3 days Advisory disclosed
02/20/2026 +0 days VulDB entry created
02/20/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-fqx6-693c-f55g
Status: Confirmed

CVE: CVE-2026-27016 (🔒)
GCVE (CVE): GCVE-0-2026-27016
GCVE (VulDB): GCVE-100-347062

Entryinfo

Created: 02/20/2026 07:58
Changes: 02/20/2026 07:58 (69)
Complete: 🔍
Cache ID: 216::103