Is CVE-2026-38570 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-38570 being exploited in the wild.

How severe is CVE-2026-38570?

Informational severity, with a CVSS score of 7.5, published 4 June 2026.

Which products and versions are affected?

BACnet Stack Project BACnet Stack 1.3.1.

Is there a fix for CVE-2026-38570?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-38570 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-38570?

Check whether you run BACnet Stack Project BACnet Stack at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-38570: BACnet Stack out-of-bounds read in bacnet_tag_number_decode

CVE-2026-38570 · Severity: info · CVSS 7.5 · Published 2026-06-04

The BACnet Stack library, which provides communication services for building automation and control networks, contains a vulnerability in its data decoding component. An attacker can send a specially crafted network message to trigger a crash in the software. This results in a denial-of-service condition, potentially disrupting the monitoring and control of building systems like HVAC, lighting, and access control.

Technologies: BACnet Stack Project BACnet Stack. Vendors: BACnet Stack Project.

Quick answers

Is CVE-2026-38570 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-38570 being exploited in the wild.
How severe is CVE-2026-38570?: Informational severity, with a CVSS score of 7.5, published 4 June 2026.
Which products and versions are affected?: BACnet Stack Project BACnet Stack 1.3.1.
Is there a fix for CVE-2026-38570?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-38570 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-38570?: Check whether you run BACnet Stack Project BACnet Stack at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

An out-of-bounds (OOB) read vulnerability exists in BACnet Stack 1.3.1 within the bacnet_tag_number_decode function. The root cause is a failure in bacapp_decode_application_data() to validate an oversized extended application length against the actual remaining bytes in the APDU. This malformed length is passed through bacapp_decode_data() to host_n_port_decode(), which subsequently triggers an invalid memory read in bacnet_tag_number_decode(). A remote, unauthenticated attacker can exploit this by sending a malformed UCOV (Unconfirmed Change of Value) or property-value payload, leading to a segmentation fault and denial of service.

Affected products

BACnet Stack Project BACnet Stack 1.3.1

Timeline

2026-06-04: disclosed: Vulnerability reported via GitHub Issues and published to NVD.

References

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.