CVE-2021-30712: 
macOS vulnerability analysis and mitigation

A logic issue in Apple's macOS operating systems was identified as CVE-2021-30712. The vulnerability was discovered by Aleksandar Nikolic of Cisco Talos and affected macOS Big Sur, Catalina, and Mojave operating systems. The issue was fixed in macOS Big Sur 11.4, Security Update 2021-003 Catalina, and Security Update 2021-004 Mojave, released on May 24, 2021 (Apple Security, Apple Catalina, Apple Mojave).

The vulnerability was identified as a logic issue in the smbx component of macOS that was addressed with improved state management. The issue 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 (NVD).

When exploited, this vulnerability could allow a remote attacker to cause unexpected application termination or execute arbitrary code on the affected system (Apple Security).

Apple addressed this vulnerability by improving state management in the affected systems. Users should update to macOS Big Sur 11.4, Security Update 2021-003 Catalina, or Security Update 2021-004 Mojave depending on their operating system version (Apple Security, Apple Catalina, Apple Mojave).