CVE-2026-20700 Apple Multiple Buffer Overflow Vulnerability
Apple iOS, macOS, tvOS, watchOS, and visionOS contain an improper restriction of operations within the bounds of a memory buffer vulnerability that could allow an attacker with memory write the capability to execute arbitrary code.
From the CISA KEV catalogue version 2026.11.06, with Cybergen analysis. Updated 6 Nov 2026.
Should You Worry?
- CISA confirmed exploitation in the wild and added it to the Known Exploited Vulnerabilities catalogue on 12 Feb 2026.
- Rated High severity (CVSS 7.8, scored by CISA).
- It has been in the catalogue for 267 days. Systems still unpatched now have almost certainly been scanned for it.
What It Is
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.
Affected Versions
| Product | Versions |
|---|---|
| Apple iOS and iPadOS | before 26.3 |
| Apple macOS | before 26.3 |
| Apple tvOS | before 26.3 |
| Apple visionOS | before 26.3 |
| Apple watchOS | before 26.3 |
From the public CVE record, as supplied by the vendor. Always confirm against the vendor advisory.
What To Do Now
- 1
Find it
Search your asset inventory and external attack surface for Apple Multiple Products. Include cloud images, appliances and anything a supplier runs for you.
Attack Surface Management - 2
Fix it
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Vulnerability Management - 3
Hunt for compromise
If an affected system was reachable before you patched, assume it may have been hit. Check logs, new accounts, web shells and outbound connections from the date of exposure.
Incident Response - 4
Prove it is fixed
Rescan or test the system after patching. Upgrades that fail silently and forgotten secondary instances are common.
Penetration Testing
The Compliance Clock
General guidance, not legal advice. Your obligations depend on your sector, scope and jurisdiction.
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