---
id: CVE-2025-11618
title: "A missing validation check in FreeRTOS-Plus-TCP's UDP/IPv6 packet processing code can lead to an invalid pointer dereference when receiving a UDP/IPv6 packet with an incorrect IP version field in the packet header.\_This issue only affect…"
summary: "A missing validation check in FreeRTOS-Plus-TCP's UDP/IPv6 packet processing code can lead to an invalid pointer dereference when receiving a UDP/IPv6 packet with an incorrect IP version field in the packet header.\_This issue only affect…"
severity: medium
cvss: 4.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L'
cwe:
  - CWE-476
vendor: amazon
product: freertos-plus-tcp
affected:
  - 'freertos-plus-tcp >= 4.0.0, < 4.3.4'
patched:
  - freertos-plus-tcp 4.3.4
published: '2025-10-10'
updated: '2026-10-08'
sourceUpdated: '2026-10-08T13:10:00.200'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-11618'
references:
  - url: 'https://aws.amazon.com/security/security-bulletins/AWS-2025-023/'
    label: ff89ba41-3aa1-4d27-914a-91399e9639e5
  - url: 'https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/releases/tag/V4.3.4'
    label: ff89ba41-3aa1-4d27-914a-91399e9639e5
  - url: >-
      https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/security/advisories/GHSA-6fh9-mqxj-hmwj
    label: ff89ba41-3aa1-4d27-914a-91399e9639e5
tags:
  - nvd
epss: 0.00338
epssPercentile: 0.25107
ingestedAt: '2026-10-08T13:42:55.085Z'
---

## Overview

A missing validation check in FreeRTOS-Plus-TCP's UDP/IPv6 packet processing code can lead to an invalid pointer dereference when receiving a UDP/IPv6 packet with an incorrect IP version field in the packet header. This issue only affects applications using IPv6.

We recommend upgrading to the latest version and ensure any forked or derivative code is patched to incorporate the new fixes.

## Affected

- `freertos-plus-tcp >= 4.0.0, < 4.3.4`

## Remediation

Upgrade past the affected range:

- `freertos-plus-tcp 4.3.4`