CVE-2026-86426criticalobserved exploitationCWE-287

CVE-2026-86426: critical vulnerability in librenms

LibreNMS before 26.8.0 Authentication Bypass via API Token Type Confusion

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85Vexday Risk Score

Patch now. It exploitation observed by VulnCheck and has a working public exploit.

ssvc Actcvss 9.2epss 4.4%
from disclosure to weapon48 days
Published on NVDSep 7
1st PoC+48d
VulnCheck+51d
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:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Affected products
librenms · librenms
⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
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