# CVE-2026-45341: BACnet Stack NULL pointer dereference in WriteProperty

Source: https://junglewise.ai/threats/cve-2026-45341-bacnet-stack-is-a-bacnet-open-source-protocol-stack-c-library-for  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-12. Updated: 2026-11-12  
License: CC BY 4.0 with a link back

CVE-2026-45341 · Severity: high · CVSS 7.5 · Published 2026-11-12

BACnet Stack is a C library used in building automation systems to enable communication between HVAC, lighting, and security equipment. A crafted network request can crash a server running this library, causing a denial of service that disrupts facility control and monitoring.

Technologies: [BACnet Stack](https://junglewise.ai/threats/technologies/bacnet-stack-bacnet-stack). Vendors: [BACnet Stack](https://junglewise.ai/threats/vendors/bacnet-stack).

## Quick answers

**Is CVE-2026-45341 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-45341 being exploited in the wild.

**How severe is CVE-2026-45341?** High severity, with a CVSS score of 7.5, published 12 November 2026.

**Which products and versions are affected?** BACnet Stack 1.4.0 to 1.4.3, 1.5.0.

**Is there a fix for CVE-2026-45341?** Yes: fixed in 1.4.4, 1.5.1. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-45341 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-45341?** Check whether you run 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.

## How to fix

- Fixed in 1.4.4, 1.5.1

## Technical details

A NULL pointer dereference occurs in bacnet_device_object_reference_decode() when processing a WriteProperty request that updates OBJECT_STRUCTURED_VIEW / PROP_SUBORDINATE_LIST. The vulnerable code passes NULL as the value parameter to bacnet_device_object_reference_decode(), which then attempts to write to value->deviceIdentifier without null checking, causing a segmentation fault. The attack requires network access to send a crafted BACnet APDU.

## Affected products

- BACnet Stack BACnet Stack 1.4.0 to 1.4.3, 1.5.0

## Timeline

- 2026-07-05: disclosed
- 2026-11-12: advisory

## References

- [https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-fv2r-c2m2-7qhh](https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-fv2r-c2m2-7qhh)

## Related threats

- [BACnet Stack buffer overflow in EPICS app](https://junglewise.ai/threats/cve-2026-52786-bacnet-stack-is-a-bacnet-open-source-protocol-stack-c-library-for)
- [BACnet Stack stack buffer overflow in life-safety-zone property read](https://junglewise.ai/threats/cve-2026-47711-bacnet-stack-is-a-bacnet-open-source-protocol-stack-c-library-for)
- [BACnet Stack stack-based buffer overflow in RemoveListElement](https://junglewise.ai/threats/cve-2026-47259-bacnet-stack-is-a-bacnet-open-source-protocol-stack-c-library-for)
- [BACnet Stack stack-based buffer overflow in Notification Class AddListElement](https://junglewise.ai/threats/cve-2026-47258-bacnet-stack-is-a-bacnet-open-source-protocol-stack-c-library-for)
- [BACnet Stack restore logic flaw causes data loss](https://junglewise.ai/threats/cve-2026-47257-bacnet-stack-is-a-bacnet-open-source-protocol-stack-c-library-for)