---
id: CVE-2026-20657
title: A buffer overflow issue was addressed with improved memory handling
summary: >-
  A buffer overflow issue was addressed with improved memory handling. This
  issue is fixed in iOS 18.7.7 and iPadOS 18.7.7, iOS 26.4 and iPadOS 26.4,
  macOS Sequoia 15.7.5, macOS Sonoma 14.8.5, macOS Tahoe 26.4, visionOS 26.4.
  Parsing a mal…
severity: medium
cvss: 6.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H'
cvssSource: adp
vendor: Apple
product: iOS and iPadOS
affected:
  - ios_and_ipados < 18.7.7
  - ios_and_ipados < 26.4
  - macOS < 14.8.5
  - macOS < 15.7.5
  - macOS < 26.4
  - visionOS < 26.4
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-03-26T13:50:36.656387Z'
published: '2026-03-25'
updated: '2026-10-26'
sourceUpdated: '2026-10-26T20:36:41.111Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-20657'
references:
  - url: 'https://support.apple.com/en-us/126792'
  - url: 'https://support.apple.com/en-us/126793'
  - url: 'https://support.apple.com/en-us/126794'
  - url: 'https://support.apple.com/en-us/126795'
  - url: 'https://support.apple.com/en-us/126796'
  - url: 'https://support.apple.com/en-us/126799'
tags:
  - cve.org
epss: 0.00562
epssPercentile: 0.4653
ingestedAt: '2026-10-27T16:11:58.880Z'
---

## Overview

A buffer overflow issue was addressed with improved memory handling. This issue is fixed in iOS 18.7.7 and iPadOS 18.7.7, iOS 26.4 and iPadOS 26.4, macOS Sequoia 15.7.5, macOS Sonoma 14.8.5, macOS Tahoe 26.4, visionOS 26.4. Parsing a maliciously crafted file may lead to an unexpected app termination.

## Affected

- `ios_and_ipados < 18.7.7`
- `ios_and_ipados < 26.4`
- `macOS < 14.8.5`
- `macOS < 15.7.5`
- `macOS < 26.4`
- `visionOS < 26.4`

## Remediation

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