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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| librenms | librenms | < 26.8.0 | 26.8.0 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
GitHub 1 repository
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Guila95/CVE-2026-86426 ★ 0 · Oct 25, 2026
CVE-2026-86426 CHECK
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Automated scanner template
A ready-made Nuclei template detects this vulnerability automatically. Vulnerabilities with public scanner templates are typically probed across the internet soon after the template appears — exposed systems should be patched first.
- LibreNMS <= 26.7.0 - Unauthenticated API Access http/cves/2026/CVE-2026-86426.yaml
Source: projectdiscovery/nuclei-templates (MIT) — updated daily. Only links are listed.
References
- GitHub Security Advisory (GHSA-cvq8-gqfq-3mvg) vendor-advisory
- VulnCheck Advisory: LibreNMS before 26.8.0 Authentication Bypass via API Token Type Confusion third-party-advisory