CVE-2020-3840: 
macOS vulnerability analysis and mitigation

CVE-2020-3840 is a security vulnerability discovered in Apple's IPSec component that affects multiple Apple operating systems including iOS, iPadOS, macOS, and tvOS. The vulnerability was disclosed and patched in January 2020 as part of Apple's security updates. The issue was identified by security researcher @littlelailo (Apple Support).

The vulnerability is an off-by-one issue that existed in the handling of racoon configuration files in the IPSec component. The security flaw was addressed through improved bounds checking. This affected iPhone 6s and later, iPad Air 2 and later, iPad mini 4 and later, iPod touch (7th generation), macOS Catalina 10.15.2, Apple TV 4K and Apple TV HD (Apple Support, Apple Support).

If exploited, loading a maliciously crafted racoon configuration file could lead to arbitrary code execution on the affected system (Apple Support).

Apple addressed this vulnerability by releasing security updates in iOS 13.3.1, iPadOS 13.3.1, macOS Catalina 10.15.3, Security Update 2020-001 Mojave, Security Update 2020-001 High Sierra, and tvOS 13.3.1. Users should update their devices to these versions or later to protect against this vulnerability (Apple Support, Apple Support).