CVE-2021-1767: 
macOS vulnerability analysis and mitigation

CVE-2021-1767 is a security vulnerability discovered in Apple's Model I/O component that affects macOS Big Sur 11.0.1, macOS Catalina 10.15.7, and macOS Mojave 10.14.6. The vulnerability was discovered by Mickey Jin & Junzhi Lu of Trend Micro working with Trend Micro's Zero Day Initiative and was fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, and Security Update 2021-001 Mojave released on February 1, 2021 (Apple Support).

The vulnerability is related to processing maliciously crafted images that could lead to heap corruption. The issue was addressed with improved checks in the Model I/O component. The vulnerability has been assigned 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 (NVD).

When exploited, this vulnerability could allow processing of maliciously crafted images to lead to heap corruption in the affected systems. This could potentially compromise the system's memory integrity and lead to unauthorized data access or system manipulation (Apple Support).

Apple has addressed this vulnerability by implementing improved checks in the Model I/O component. Users are advised to update to macOS Big Sur 11.2, Security Update 2021-001 Catalina, or Security Update 2021-001 Mojave to protect against this vulnerability (Apple Support).