CVE-2021-30790: 
macOS vulnerability analysis and mitigation

CVE-2021-30790 is an information disclosure vulnerability discovered in Apple's macOS operating system. The vulnerability was disclosed and patched on July 21, 2021, affecting multiple versions of macOS including Big Sur, Catalina, and Mojave. The issue was identified in the AppKit component and was discovered by researcher hjy79425575 working with Trend Micro Zero Day Initiative (Apple Security).

The vulnerability is an information disclosure issue in the AppKit component that could be triggered by opening a maliciously crafted file. The issue was addressed by removing the vulnerable code. The vulnerability has 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 is required with user interaction (NVD).

The vulnerability could lead to unexpected application termination or arbitrary code execution when opening a maliciously crafted file. This could potentially allow attackers to execute malicious code or cause application crashes on affected systems (Apple Security).

Apple addressed this vulnerability by releasing security updates for affected operating systems: macOS Big Sur 11.5, Security Update 2021-004 Catalina, and Security Update 2021-005 Mojave. Users are advised to update their systems to these versions to mitigate the vulnerability (Apple Security).