8.8 High Exploited

CVE-2020-9818 Apple iOS, iPadOS, and watchOS Out-of-Bounds Write Vulnerability

Active exploitation observed

· CISA KEV catalogue

Required action Apply updates per vendor instructions.

Ransomware campaigns Not observed so far

Weakness CWE-787

Description

An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 13.5 and iPadOS 13.5, iOS 12.4.7, watchOS 6.2.5. Processing a maliciously crafted mail message may lead to unexpected memory modification or application termination.

Affected products and versions

Product	Affected versions	Fixed in
iOS	Versions not published
iOS-1	Versions not published
watchOS	Versions not published

References

support.apple.com support.apple.com
support.apple.com support.apple.com
support.apple.com support.apple.com

Timeline

Published June 9, 2020
Added to the KEV catalogue November 3, 2021
Last modified December 20, 2025

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