CVE-2018-4254: Apple Mac OS X

Critical severity, CVSS 9.8. EPSS: 1.3% chance of exploitation in the next 30 days.

In macOS High Sierra before 10.13.5, an input validation issue existed in the kernel. This issue was addressed with improved input validation.

Affected products

• Apple Mac OS X: before 10.13.5 (fixed in 10.13.5)

Published 2019-01-11. Last modified 2026-06-17.