iOS 14.4.2 and iPadOS 14.4.2
iPhone 6s and later, iPad Pro (all models), iPad Air 2 and later, iPad 5th generation and later, iPad mini 4 and later, and iPod touch (7th generation)

provides important security updates and is recommended for all users.

iOS 12.5.2
iPhone 5s, iPhone 6, iPhone 6 Plus, iPad Air, iPad mini 2, iPad mini 3, and iPod touch (6th generation)

provides important security updates and is recommended for all users.

watchOS 7.3.3
Apple Watch Series 3 and later

Primarily a Security for WebKit:

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.

Description: This issue was addressed by improved management of object lifetimes.

CVE-2021-1879: Clement Lecigne of Google Threat Analysis Group and Billy Leonard of Google Threat Analysis Group