---
id: "CVE-2026-52789"
page: "https://infrastack.ai/live/CVE-2026-52789"
kind: "vulnerability"
aliases: ["CVE-2026-52789"]
title: "BACnet Stack: malformed ReadPropertyMultiple request hangs the handler"
severity: "high"
cvss: 7.5
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["bacnet", "c", "embedded", "package"]
not_affected_if: ["not-using-bacnet-stack"]
published_at: "2026-11-13T16:19:02+00:00"
first_seen_at: "2026-11-13T16:47:34+00:00"
updated_at: "2026-11-13T16:48:35+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-52789", "first_seen_at": "2026-11-13T16:47:34+00:00"}]
exploit_sources: []
---

# BACnet Stack: malformed ReadPropertyMultiple request hangs the handler

Link for people: https://infrastack.ai/live/CVE-2026-52789 (this .md is for agents)

BACnet Stack is a C library for building BACnet devices. A malformed ReadPropertyMultiple request missing its closing tags makes the handler loop forever, so the device stops responding.

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

## How to check

- Check the version of the BACnet Stack library your device or application is built with, against the fixed versions below.
- Look for the `handler_read_property_multiple` function in your build to confirm the library is included.

## Fix

- Upgrade BACnet Stack to `1.4.5`, `1.5.1`, or `1.6.0`, matching your release line.

## Timeline

- 2026-11-13T16:47:34+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-52789

## Documents

- [advisory] Vendor advisory: github.com https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-4rf9-4vgq-5gcw

## 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 Denial of Service (DoS) vulnerability exists in the BACnet stack's ReadPropertyMultiple (RPM) handler. When processing a malformed RPM request packet that lacks the expected closing tags, the function handler_read_property_multiple enters an infinite loop. This issue has been patched in versions 1.4.5, 1.5.1, and 1.6.0.

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