Apple released iOS 14.4.2 last week, and as is traditional, Apple has now stopped signing iOS 14.4.1, making downgrading to that version of iOS no longer possible.
An Apple security support document says iOS 14.4.1 that the updates fix a WebKit bug that could allow maliciously crafted web content to arbitrarily execute code.
Apple has said that the vulnerability addressed in iOS 14.4.2 has been actively exploited in the wild, so those who have not updated are urged to do so.
According to Apple’s release notes, the update offers important security updates and is recommended for all users. An Apple security support document says that the update fixes a vulnerability that was actively exploited.
Impact: Processing maliciously crafted web content may lead to universal cross site scripting. Apple is aware of a report that this issue may have been actively exploited.
Apple has fixed the issue by improved management of object lifetimes.
Apple is known to routinely stop signing older versions of operating systems after it releases a public update, as part of an effort to encourage users to keep their devices’ operating systems up to date. Restoring devices to older iOS builds is common for users with jailbroken devices.