by Kastro
Paper/Archive/CVE-2026-86426

CVE-2026-86426

librenms librenms — LibreNMS before 26.8.0 Authentication Bypass via API Token Type Confusion

EPSS 4%public exploitCVSS 9.8
critical.is priorityof 100
58
CVSS 9.8 (NVD)9.8 / 10 × 3029.4Not in CISA KEV+300.0EPSS percentile 91.2.912 × 2018.2Exploit: SSVC poc+1010.0SSVC exploitation: poc+100.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
librenms< 26.8.026.8.0CNA

Scores by source

NVD9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
VulnCheck (CNA)9.2CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CISA ADPSSVCExploitation: poc · Automatable: no · Technical impact: total

References

exploitgithub.com/librenms/librenms/security/advisories/GHSA-cvq8-gqfq-3mvgwriteupvulncheck.com/advisories/librenms-before-26.8.0-authentication-bypass-via-api-token-type-confusion