CVE-2021-30799: Apple iPhone OS

High severity, CVSS 8.8. EPSS: 2.3% chance of exploitation in the next 30 days.

Multiple memory corruption issues were addressed with improved memory handling. This issue is fixed in iOS 14.7, macOS Big Sur 11.5, Security Update 2021-004 Catalina, Security Update 2021-005 Mojave. Processing maliciously crafted web content may lead to arbitrary code execution.

Affected products

• Apple iPhone OS: before 14.7 (fixed in 14.7)
• Apple Mac OS X: from 10.14, up to and including 10.14.6; from 10.15, before 10.15.7 (fixed in 10.15.7); version 10.14.6 only; version 10.15.6 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.