---
id: "CVE-2026-62973"
page: "https://infrastack.ai/live/CVE-2026-62973"
kind: "vulnerability"
aliases: ["CVE-2026-62973"]
title: "BACnet Stack: malicious device reply causes out-of-bounds read in readpropm"
severity: "high"
cvss: 7.5
epss: null
exploited: false
status: "open"
category: "package"
products: [{"name": "bacnet-stack", "fixed": [], "affected": "", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["bacnet-stack", "building-automation", "c", "embedded", "package"]
not_affected_if: ["no-readpropm-built", "trusted-network-only"]
published_at: "2026-11-13T16:19:28+00:00"
first_seen_at: "2026-11-13T16:47:35+00:00"
updated_at: "2026-11-13T16:48:32+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-62973", "first_seen_at": "2026-11-13T16:47:35+00:00"}]
exploit_sources: []
---

# BACnet Stack: malicious device reply causes out-of-bounds read in readpropm

Link for people: https://infrastack.ai/live/CVE-2026-62973 (this .md is for agents)

BACnet Stack is a C library for the BACnet building-automation protocol, and its readpropm client can be made to read past a global receive buffer. A malicious BACnet/IP peer that answers a ReadPropertyMultiple request with a malformed but structurally valid reply can trigger the over-read.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:bacnet-stack affected range not listed fixed no fixed version listed

## How to check

- Check the BACnet Stack version in use against the fixed versions listed below.
- Look for the `apps/readpropm` client built from the bacnet-stack source in your tree or firmware.

## Fix

- Move to `1.4.5`, `1.5.1`, or `1.6.0` (fixed versions per the advisory, matching each release line).

## Timeline

- 2026-11-13T16:47:35+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-62973

## Documents

- [advisory] Vendor advisory: github.com https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-3xxw-jfwm-rq9c

## From the sources

BACnet Stack is a BACnet open source protocol stack C library for embedded systems. Prior to versions 1.4.5, 1.5.1, and 1.6.0, a remote out-of-bounds read exists in the official BACnet client application apps/readpropm in bacnet-stack commit e2bdbf6. When readpropm sends a legitimate ReadPropertyMultiple request to a malicious BACnet/IP peer, the peer can reply with a malformed but structurally valid ReadPropertyMultiple-ACK that drives the client into a global-buffer-overflow read on the global receive buffer Rx_Buf. This issue has been patched in versions 1.4.5, 1.5.1, and 1.6.0.

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