---
id: "CVE-2026-75492"
page: "https://infrastack.ai/live/CVE-2026-75492"
kind: "vulnerability"
aliases: ["CVE-2026-75492"]
title: "Cudy TR3000 router: unauthenticated UDP packet overflows stack, crashes service"
severity: "high"
cvss: 8.7
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: []
ecosystems: []
tags: ["cudy-tr3000", "home-router", "infrastructure", "tr-069"]
not_affected_if: ["firmware-2.5.42-or-later", "stun-client-disabled"]
published_at: "2026-11-13T10:18:16+00:00"
first_seen_at: "2026-11-13T10:47:35+00:00"
updated_at: "2026-11-13T10:49:08+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-75492", "first_seen_at": "2026-11-13T10:47:35+00:00"}]
exploit_sources: []
---

# Cudy TR3000 router: unauthenticated UDP packet overflows stack, crashes service

Link for people: https://infrastack.ai/live/CVE-2026-75492 (this .md is for agents)

Cudy TR3000 routers before firmware 2.5.42 have a stack buffer overflow in the stun_client TR-111 UDP connection request parser. A single crafted UDP datagram sent without authentication can overflow a 10-byte stack buffer and crash stun_client, causing denial of service.

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

## How to check

- Check the firmware version on the router's admin page; versions below `2.5.42` are in the stated range
- Check whether TR-069/TR-111 connection request handling (stun_client) is enabled on the device

## Fix

- Cudy TR3000: upgrade to firmware `2.5.42` or later

## Timeline

- 2026-11-13T10:47:35+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-75492

## Documents

- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/cudy-tr3000-before-2.5.42-stack-buffer-overflow-via-stun-client-udp-parser

## From the sources

Cudy TR3000 before 2.5.42 contains an unauthenticated stack buffer overflow vulnerability in the stun_client TR-111 UDP Connection Request parser that parses requests before verifying username or HMAC. Remote attackers can send a single crafted UDP datagram lacking a space in the request line, causing strncpy() to overflow a 10-byte stack buffer and crash stun_client for denial of service.

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_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_