CVE-2026-86426

LibreNMS before 26.8.0 contains an authentication bypass vulnerability in the REST API that allows unauthenticated attackers to access protected endpoints by sending numeric values instead of string tokens. Attackers can exploit MySQL type coercion by sending small integers like 0 through 9 to match token hashes, gaining access to API functionality including device credentials and administrative features that enable remote code execution through alert templates.

CVSS

No CVSS.

References

Link	Resource
https://github.com/librenms/librenms/security/advisories/GHSA-cvq8-gqfq-3mvg
https://www.vulncheck.com/advisories/librenms-before-26.8.0-authentication-bypass-via-api-token-type-confusion
https://github.com/librenms/librenms/security/advisories/GHSA-cvq8-gqfq-3mvg

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-07 13:20

Updated : 2026-09-08 19:57

NVD link : CVE-2026-86426

Mitre link : CVE-2026-86426

CVE.ORG link : CVE-2026-86426

JSON object : View

Products Affected

No product.

CWE

CWE-287

Improper Authentication

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