CVE-2021-1805: Apple Mac OS X

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

An out-of-bounds write was addressed with improved input validation. This issue is fixed in macOS Big Sur 11.2.1, macOS Catalina 10.15.7 Supplemental Update, macOS Mojave 10.14.6 Security Update 2021-002. An application may be able to execute arbitrary code with kernel privileges.

Affected products

• Apple Mac OS X: from 10.14, before 10.14.6 (fixed in 10.14.6); from 10.15, before 10.15.7 (fixed in 10.15.7); version 10.14.6 only; version 10.15.7 only
• Apple macOS: from 11.0, before 11.2 (fixed in 11.2)

Published 2021-04-02. Last modified 2026-06-17.