CVE-2021-30830: Apple Mac OS X

High severity, CVSS 7.8. EPSS: 1.1% chance of exploitation in the next 30 days.

A memory corruption issue was addressed with improved memory handling. This issue is fixed in Security Update 2021-005 Catalina, macOS Big Sur 11.6. A malicious application may be able to execute arbitrary code with kernel privileges.

Affected products

• Apple Mac OS X: from 10.15, up to and including 10.15.6; version 10.15.7 only
• Apple macOS: from 11.0, before 11.6 (fixed in 11.6)

Published 2021-10-19. Last modified 2026-06-17.