CVE-2021-1777: 
macOS vulnerability analysis and mitigation

CVE-2021-1777 is a security vulnerability that affects multiple Apple operating systems including macOS Big Sur, iOS 14.4, iPadOS 14.4, watchOS 7.3, and tvOS 14.4. The vulnerability was discovered by Xingwei Lin of Ant Security Light-Year Lab and was addressed in updates released on January 26, 2021. The issue involves processing maliciously crafted images that could lead to arbitrary code execution (Apple Security).

The vulnerability is related to image processing functionality and was addressed with improved checks in the ImageIO component. It received a CVSS v3.1 base score of 7.8 (HIGH) with the vector string CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H, indicating local access requirements but high impact potential (NVD).

If exploited, this vulnerability could allow processing of a maliciously crafted image to lead to arbitrary code execution on the affected system. This could potentially compromise user data and system security (Apple Security).

Apple addressed this vulnerability in the following updates: macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, watchOS 7.3, tvOS 14.4, iOS 14.4 and iPadOS 14.4. Users should update their devices to these versions or later to protect against this vulnerability (Apple Security).