"Clear History and Website Data" did not clear the history. The issue was addressed with improved data deletion. This issue is fixed in macOS Big Sur 11.1, Security Update 2020-001 Catalina, Security Update 2020-007 Mojave, iOS 14.3 and iPadOS 14.3, tvOS 14.3. A user may be unable to fully delete browsing history.

This issue was addressed with improved iframe sandbox enforcement. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave. Maliciously crafted web content may violate iframe sandboxing policy.

A code execution vulnerability exists in the AudioSourceProviderGStreamer functionality of Webkit WebKitGTK 2.30.1. A specially crafted web page can lead to a use after free.

A use after free issue was addressed with improved memory management. This issue is fixed in macOS Big Sur 11.0.1, watchOS 7.1, iOS 14.2 and iPadOS 14.2, iCloud for Windows 11.5, Safari 14.0.1, tvOS 14.2, iTunes 12.11 for Windows. Processing maliciously crafted web content may lead to arbitrary code execution.

An exploitable use-after-free vulnerability exists in WebKitGTK browser version 2.30.1 x64. A specially crafted HTML web page can cause a use-after-free condition, resulting in a remote code execution. The victim needs to visit a malicious web site to trigger this vulnerability.

An input validation issue was addressed with improved input validation. This issue is fixed in iOS 14.0 and iPadOS 14.0, tvOS 14.0, watchOS 7.0, Safari 14.0, iCloud for Windows 11.4, iCloud for Windows 7.21. Processing maliciously crafted web content may lead to a cross site scripting attack.

A use after free issue was addressed with improved memory management. This issue is fixed in Safari 14.0. Processing maliciously crafted web content may lead to arbitrary code execution.

A type confusion issue was addressed with improved memory handling. This issue is fixed in Safari 14.0. Processing maliciously crafted web content may lead to arbitrary code execution.

The bubblewrap sandbox of WebKitGTK and WPE WebKit, prior to 2.28.3, failed to properly block access to CLONE_NEWUSER and the TIOCSTI ioctl. CLONE_NEWUSER could potentially be used to confuse xdg-desktop-portal, which allows access outside the sandbox. TIOCSTI can be used to directly execute commands outside the sandbox by writing to the controlling terminal's input buffer, similar to CVE-2017-5226.

A use-after-free issue exists in WebKitGTK before 2.28.1 and WPE WebKit before 2.28.1 via crafted web content that allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption and application crash).