CVE-2019-20503

A race condition was addressed with improved state handling. This issue is fixed in iOS 13.5 and iPadOS 13.5, macOS Catalina 10.15.5, tvOS 13.4.5, watchOS 6.2.5. An application may be able to gain elevated privileges.

By carefully crafting promise resolutions, it was possible to cause an out-of-bounds read off the end of an array resized during script execution. This could have led to memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 68.6, Firefox < 74, Firefox < ESR68.6, and Firefox ESR < 68.6.

Insufficient policy enforcement in extensions in Google Chrome prior to 80.0.3987.149 allowed an attacker who convinced a user to install a malicious extension to bypass site isolation via a crafted Chrome Extension.