"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.
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.
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.