CVSS 4.0
7.7 highCVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NCVE-2026-102537 bacnet-stack BACnet/SC node always accepts a self-signed hub cert, so an attacker can MITM it
High (7.7) in bacnet-stack bacnet-stack.
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BACnet Stack is a BACnet open source protocol stack C library for embedded systems. Prior to versions 1.4.6, 1.5.2, and 1.6.1, bws_cli_connect() in ports/linux/websocket-cli.c loads the trusted CA cert into the libwebsockets context, then always sets LCCSCF_ALLOW_SELFSIGNED in the connection flags. So lws accepts any self-signed hub certificate, whether or not it chains to the loaded CA. A BACnet/SC node finishes the TLS handshake to a rogue hub that presents a self-signed cert. It then hands the attacker its identity (VMAC, UUID) and all later BACnet traffic. This issue has been patched in versions 1.4.6, 1.5.2, 1.6.1, and 1.7.0.
Severity
- CWE
- CWE-295 Improper Certificate Validation
- OWASP Top 10
- A07:2025 Authentication Failures
- Published
- Modified
- Assigned by
- GitHub_M (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| bacnet-stack | < 1.4.6 |
| bacnet-stack | >= 1.5.0, < 1.5.2 |
| bacnet-stack | >= 1.6.0, < 1.6.1 |
Attack patterns (CAPEC)
- CAPEC-459 Creating a Rogue Certification Authority Certificate Likelihood: Medium · Severity: Very High
- CAPEC-475 Signature Spoofing by Improper Validation Likelihood: Low · Severity: High
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.