---
id: "CVE-2026-89409"
kind: "vulnerability"
aliases: ["CVE-2026-89409"]
title: "Z-Wave SDK: missing checks let joined devices remove network nodes"
severity: "medium"
cvss: 5.3
epss: 0.00269
exploited: false
status: "open"
category: "infrastructure"
products: []
ecosystems: []
tags: ["embedded", "infrastructure", "iot", "z-wave"]
not_affected_if: ["devices-running-newer-sdk", "no-untrusted-joined-nodes"]
published_at: "2026-10-22T14:17:51+00:00"
first_seen_at: "2026-10-23T21:57:31+00:00"
updated_at: "2026-10-25T04:20:19+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-89409", "first_seen_at": "2026-10-23T21:57:31+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-89409", "first_seen_at": "2026-10-24T07:15:51+00:00"}]
---

# Z-Wave SDK: missing checks let joined devices remove network nodes

Z-Wave SDK 8.1.1 and earlier (700/800 series) and 6.85.02 and earlier (500 series) fail to validate the ZWAVE_CMD_NODES_EXIST handler. A device already on the network can send messages that cause other nodes to be removed from the network.

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

## How to check

- unknown

## Fix

- unknown

## Timeline

- 2026-10-23T21:57:31+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-89409
- 2026-10-24T07:15:51+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-89409

## From the sources

In Z-Wave SDK 8.1.1 and earlier (for 700/800 series devices) and 6.85.02 and earlier (for 500 series devices), missing checks in the ZWAVE_CMD_NODES_EXIST handler can result in nodes being removed from the network. These messages must come from a device that has already joined the network.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_