---
id: "CVE-2026-120281"
kind: "vulnerability"
aliases: ["CVE-2026-120281"]
title: "WAVLINK WN536AX6-A router: remote stack overflow in OpenVPN handler"
severity: "critical"
cvss: 10.0
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: [{"name": "WN536AX6-A", "fixed": [], "affected": "V260507", "ecosystem": "vendor"}]
ecosystems: []
tags: ["home-router", "infrastructure", "no-auth", "openvpn", "wavlink", "wn536ax6-a"]
not_affected_if: ["different-firmware", "different-model"]
published_at: "2026-11-02T01:17:27+00:00"
first_seen_at: "2026-11-02T01:23:19+00:00"
updated_at: "2026-11-02T01:24:59+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-120281", "first_seen_at": "2026-11-02T01:23:19+00:00"}, {"source": "analyst", "url": null, "first_seen_at": "2026-11-02T01:24:59+00:00"}]
---

# WAVLINK WN536AX6-A router: remote stack overflow in OpenVPN handler

WAVLINK WN536AX6-A firmware V260507 copies the openvpn_ip argument with strcpy into a stack buffer in /protocol.csp. VulDB says it can be attacked remotely without authentication and a public proof-of-concept exists. No exploitation in the wild is reported and no fixed firmware is known.

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

## Affected

- vendor:WN536AX6-A affected V260507 fixed ?

## How to check

- Check the firmware version on the router admin page; V260507 is the version reported vulnerable (other versions untested/unknown).
- Per VulDB, exploitation needs no authentication. Whether OpenVPN must be enabled for the request to reach the code is not stated by any source; treat the router as exposed if its web interface (/protocol.csp) is reachable from untrusted networks.
- Disable remote/WAN access to the router admin page.

## Timeline

- 2026-11-02T01:23:19+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-120281
- 2026-11-02T01:24:59+00:00 analyst — VulDB (secondary, CNA) says remote, no auth, public PoC on GitHub (link not shown on free page). WAVLINK advisory index has no entry for this CVE and no fix; vendor said to be contacted. OpenVPN-enablement requirement unconfirmed. Nothing marked verified (no vendor primary). Sibling CVEs 120276-120280 hit same model.

## Documents

- [describes] VulDB VDB-429625: WAVLINK WN536AX6-A openvpn_ip stack overflow https://vuldb.com/vuln/429625
- [mentions] WAVLINK Security Advisory index (does not list this CVE) https://docs.wavlink.xyz/Security_Advisory/

## From the sources

A vulnerability was found in WAVLINK WN536AX6-A V260507. This affects the function strcpy of the file /protocol.csp of the component OpenVPN Handler. The manipulation of the argument openvpn_ip results in stack-based buffer overflow. The attack may be launched remotely. The exploit has been made public and could be used. The vendor was contacted early about this disclosure.

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