---
id: CVE-2025-7403
title: >-
  Unsafe handling in bt_conn_tx_processor causes a use-after-free, resulting in
  a write-before-zero
summary: >-
  Unsafe handling in bt_conn_tx_processor causes a use-after-free, resulting in
  a write-before-zero. The written 4 bytes are attacker-controlled, enabling
  precise memory corruption.
severity: high
cvss: 7.6
cvssVector: 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H'
cwe:
  - CWE-123
vendor: zephyrproject
product: zephyr
affected:
  - zephyr <= 4.1.0
published: '2025-09-19'
updated: '2026-10-13'
sourceUpdated: '2026-10-13T20:17:01.040'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-7403'
references:
  - url: >-
      https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-9r46-cqqw-6j2j
    label: vulnerabilities@zephyrproject.org
tags:
  - nvd
epss: 0.00208
epssPercentile: 0.10097
ingestedAt: '2026-10-13T20:53:44.533Z'
---

## Overview

Unsafe handling in bt_conn_tx_processor causes a use-after-free, resulting in a write-before-zero. The written 4 bytes are attacker-controlled, enabling precise memory corruption.

## Affected

- `zephyr <= 4.1.0`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.