8.8 High Exploited

CVE-2021-30858 Apple iOS, iPadOS, macOS Use-After-Free Vulnerability

Active exploitation observed

· CISA KEV catalogue

Required action Apply updates per vendor instructions.

Ransomware campaigns Not observed so far

Weakness CWE-416

Description

A use after free issue was addressed with improved memory management. This issue is fixed in iOS 14.8 and iPadOS 14.8, macOS Big Sur 11.6. Processing maliciously crafted web content may lead to arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited.

Affected products and versions

Product	Affected versions	Fixed in
macOS 11.6	earliest → < 11.6	11.6
iOS 14.8	earliest → < 14.8	14.8

References

support.apple.com support.apple.com
support.apple.com support.apple.com
20210917 APPLE-SA-2021-09-13-3 macOS Big Sur 11.6 seclists.org
20210917 APPLE-SA-2021-09-13-1 iOS 14.8 and iPadOS 14.8 seclists.org
20210917 APPLE-SA-2021-09-13-5 Safari 14.1.2 seclists.org
[oss-security] 20210920 WebKitGTK and WPE WebKit Security Advisory WSA-2021-0005 www.openwall.com
FEDORA-2021-c00e45b6c0 lists.fedoraproject.org
20210921 APPLE-SA-2021-09-20-6 Additional information for APPLE-SA-2021-09-13-1 iOS 14.8 and iPadOS 14.8 seclists.org
20210921 APPLE-SA-2021-09-20-7 Additional information for APPLE-SA-2021-09-13-3 macOS Big Sur 11.6 seclists.org
DSA-4975 www.debian.org
DSA-4976 www.debian.org
support.apple.com support.apple.com
20210924 APPLE-SA-2021-09-23-1 iOS 12.5.5 seclists.org
FEDORA-2021-edf6957b7d lists.fedoraproject.org
[oss-security] 20211026 WebKitGTK and WPE WebKit Security Advisory WSA-2021-0006 www.openwall.com
[oss-security] 20211027 Re: WebKitGTK and WPE WebKit Security Advisory WSA-2021-0006 www.openwall.com
[oss-security] 20211027 Re: WebKitGTK and WPE WebKit Security Advisory WSA-2021-0006 www.openwall.com
[oss-security] 20211027 Re: WebKitGTK and WPE WebKit Security Advisory WSA-2021-0006 www.openwall.com

Timeline

Published August 24, 2021
Added to the KEV catalogue November 3, 2021
Last modified October 21, 2025

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