---
id: CVE-2026-43748
title: An out-of-bounds write issue was addressed with improved bounds checking
summary: >-
  An out-of-bounds write issue was addressed with improved bounds checking. This
  issue is fixed in iOS 26.6 and iPadOS 26.6, macOS Sequoia 15.7.8, macOS Tahoe
  26.6. An app may be able to cause unexpected system termination.
severity: critical
cvss: 9.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-787
vendor: apple
product: macos
affected:
  - 'macos >= 15.0, < 15.7.8'
  - 'macos >= 26.0, < 26.6'
patched:
  - macos 26.6
published: '2026-07-27'
updated: '2026-09-14'
sourceUpdated: '2026-09-14T21:17:10.323'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-43748'
references:
  - url: 'https://support.apple.com/en-us/128066'
    label: product-security@apple.com
  - url: 'https://support.apple.com/en-us/128067'
    label: product-security@apple.com
  - url: 'https://support.apple.com/en-us/128071'
    label: product-security@apple.com
tags:
  - nvd
  - cve.org
epss: 0.00585
epssPercentile: 0.45783
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: total
  timestamp: '2026-07-28T14:36:06.717647Z'
ingestedAt: '2026-09-14T21:15:17.532Z'
---

## Overview

An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 26.6 and iPadOS 26.6, macOS Sequoia 15.7.8, macOS Tahoe 26.6. An app may be able to cause unexpected system termination.

## Affected

- `macos >= 15.0, < 15.7.8`
- `macos >= 26.0, < 26.6`

## Remediation

Upgrade past the affected range:

- `macos 26.6`