---
id: "CVE-2026-20700"
kind: "vulnerability"
aliases: ["CVE-2026-20700"]
title: "A memory corruption issue was addressed with improved state management"
severity: "high"
cvss: 7.8
epss: null
exploited: true
status: "open"
category: "vendor"
products: [{"name": "Apple Multiple Products", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "apple ipados", "fixed": ["26.3"], "affected": "< 26.3", "ecosystem": "vendor"}, {"name": "apple iphone os", "fixed": ["26.3"], "affected": "< 26.3", "ecosystem": "vendor"}, {"name": "apple macos", "fixed": ["26.3"], "affected": "< 26.3", "ecosystem": "vendor"}, {"name": "apple tvos", "fixed": ["26.3"], "affected": "< 26.3", "ecosystem": "vendor"}, {"name": "apple visionos", "fixed": ["26.3"], "affected": "< 26.3", "ecosystem": "vendor"}, {"name": "apple watchos", "fixed": ["26.3"], "affected": "< 26.3", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["apple", "exploited", "ios", "macos", "tvos", "vendor", "visionos", "watchos"]
not_affected_if: ["unknown"]
published_at: "2026-02-11T23:16:10+00:00"
first_seen_at: "2026-10-23T19:11:51+00:00"
updated_at: "2026-10-23T23:44:51+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2026-20700", "first_seen_at": "2026-10-23T19:11:51+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-20700", "first_seen_at": "2026-10-23T23:44:51+00:00"}]
---

# A memory corruption issue was addressed with improved state management

A memory buffer overflow in Apple iOS, macOS, tvOS, watchOS and visionOS lets an attacker who already has memory write capability run arbitrary code. CISA lists it in the Known Exploited Vulnerabilities catalog, so it is being used in real attacks.

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

## Affected

- vendor:Apple Multiple Products affected ? fixed ?
- vendor:apple ipados affected < 26.3 fixed 26.3
- vendor:apple iphone os affected < 26.3 fixed 26.3
- vendor:apple macos affected < 26.3 fixed 26.3
- vendor:apple tvos affected < 26.3 fixed 26.3
- vendor:apple visionos affected < 26.3 fixed 26.3
- vendor:apple watchos affected < 26.3 fixed 26.3

## How to check

Run the OS version check on each Apple device (Settings > General > About on iOS, or Apple menu > About This Mac on macOS) and compare with Apple's security advisory for CVE-2026-20700. The source does not list affected versions.

## Fix

Update iOS, macOS, tvOS, watchOS and visionOS to the latest release Apple has published with a fix for CVE-2026-20700. The fixed version numbers are unknown from these sources.

## Timeline

- 2026-10-23T19:11:51+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2026-20700
- 2026-10-23T23:44:51+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-20700

## From the sources

A memory corruption issue was addressed with improved state management. This issue is fixed in iOS 26.3 and iPadOS 26.3, macOS Tahoe 26.3, tvOS 26.3, visionOS 26.3, watchOS 26.3. An attacker with memory write capability may be able to execute arbitrary code. Apple is aware of a report that this issue may have been exploited in an extremely sophisticated attack against specific targeted individuals on versions of iOS before iOS 26. CVE-2025-14174 and CVE-2025-43529 were also issued in response to this report.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_