CVE-2021-30876: Apple Mac OS X

High severity, CVSS 7.1. EPSS: 0.9% chance of exploitation in the next 30 days.

An out-of-bounds read was addressed with improved bounds checking. This issue is fixed in macOS Monterey 12.0.1, Security Update 2021-007 Catalina, macOS Big Sur 11.6.1. Processing a maliciously crafted AppleScript binary may result in unexpected application termination or disclosure of process memory.

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 11.6.1 (fixed in 11.6.1); from 12.0, before 12.0.1 (fixed in 12.0.1)

Published 2021-08-24. Last modified 2026-06-17.