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TI-2026-59134 Aliases CVE-2026-86426GHSA-84cr-xjpw-q9mc

LibreNMS before 26.8.0 Authentication Bypass via API Token Type Confusion

Priority HIGH 75CWE-287Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-287.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.04358 91st percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed librenms (librenms): 26.8.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
librenmslibrenmsbefore 26.8.026.8.0Patch availableCNA
  • librenms Vendorlibrenms Affected before 26.8.0 Fixed in 26.8.0 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:librenms:librenms:*:*:*:*:*:*:*:*before 26.8.0Vulnerablelibrenms
  • cpe:2.3:a:librenms:librenms:*:*:*:*:*:*:*:* Versions before 26.8.0 Vulnerable ·librenms

Remediation

  • Fix · CNA librenms (librenms) Fixed in 26.8.0

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    librenms 26.8.0

    2 records Highest priority Priority HIGH 1 HIGH, 1 MEDIUM

    Other records, highest priority first

    • TI-2026-59135 LibreNMS before 26.8.0 Argument Injection via graph_titlePriority MEDIUM 41
    Show all 2 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-86426
  2. 2026-10-03 Alias added: GHSA-84cr-xjpw-q9mc
  3. 2026-10-14 EPSS moved to the 90th–95th percentile

References

Exploit 1

  • TI-2018-14479 LibreNMS 1.46 allows remote attackers to execute arbitrary OS commands by using the… CVSS 3.0CRITICAL 9.8
  • TI-2022-03735 Insufficient Session Expiration in librenms/librenms CVSS 3.1CRITICAL 9.8
  • TI-2022-03252 Deserialization of Untrusted Data in librenms/librenms CVSS 3.1HIGH 8.8
  • TI-2026-05445 OS command injection in librenms CVSS 4.0HIGH 8.5
  • TI-2024-34235 LibreNMS before 24.10.0 allows a remote attacker to execute arbitrary code via OS command… CVSS 3.1CRITICAL 9.1
  • TI-2023-25228 Rate limiting Bypass on login page in libreNMS CVSS 3.1HIGH 7.5
See all 105 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences