CVE-2021-30787: Apple Mac OS X

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

This issue was addressed with improved checks. This issue is fixed in macOS Big Sur 11.5, Security Update 2021-004 Catalina, Security Update 2021-005 Mojave. An application may be able to cause unexpected system termination or write kernel memory.

Affected products

• Apple Mac OS X: from 10.14, up to and including 10.14.5; from 10.15, up to and including 10.15.6; version 10.14.6 only; version 10.15.7 only
• Apple macOS: from 11.0, before 11.5 (fixed in 11.5)

Published 2021-09-08. Last modified 2026-06-17.