A memory corruption issue existed in the processing of font files. This issue was addressed with improved input validation. This issue is fixed in tvOS 14.3, iOS 14.3 and iPadOS 14.3, macOS Big Sur 11.1, Security Update 2020-001 Catalina, Security Update 2020-007 Mojave, watchOS 7.2. Processing a maliciously crafted font file may lead to arbitrary code execution.