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CVE-2026-86426

LibreNMS before 26.8.0 Authentication Bypass via API Token Type Confusion

Published: Sep 7, 2026Updated: Sep 18, 2026 Sources: CVE List NVDCWE-287
9.8CRITICAL
NVD MITRE
EPSS Score
2.1%
Top 19.0%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
Nuclei

Description

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
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Weaknesses

CWE-287

Affected Products

librenms
oss-projectaka librenms/librenms
librenmsOn-premWeb App
Enterprise Software / itsm-monitoring

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques
Initial Access
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References

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

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