BACnet Stack up to 1.4.5/1.5.1/1.6.0 TLS Handshake websocket-cli.c bws_cli_connect certificate validation

Summaryinfo

A vulnerability marked as problematic has been reported in BACnet Stack up to 1.4.5/1.5.1/1.6.0. This impacts the function bws_cli_connect of the file ports/linux/websocket-cli.c of the component TLS Handshake. Performing a manipulation results in certificate validation. This vulnerability is cataloged as CVE-2026-102537. It is possible to initiate the attack remotely. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, was found in BACnet Stack up to 1.4.5/1.5.1/1.6.0. This affects the function bws_cli_connect of the file ports/linux/websocket-cli.c of the component TLS Handshake. The manipulation with an unknown input leads to a certificate validation vulnerability. CWE is classifying the issue as CWE-295. The product does not validate, or incorrectly validates, a certificate. This is going to have an impact on integrity. The summary by CVE is:

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.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-102537 since 09/29/2026. The exploitability is told to be difficult. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1587.003 according to MITRE ATT&CK.

Upgrading to version 1.4.6, 1.5.2, 1.6.1 or 1.7.0 eliminates this vulnerability.

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Productinfo

Name

• BACnet Stack

Version

• 1.0
• 1.1
• 1.2
• 1.3
• 1.4
• 1.4.0
• 1.4.1
• 1.4.2
• 1.4.3
• 1.4.4
• 1.4.5
• 1.5
• 1.5.0
• 1.5.1
• 1.6.0

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CPE 2.2info

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