AppleCVE-2026-84578

Apple macOS: protection mechanism failure

CVE-2026-84578 · Published Sep 14, 2026 · updated Sep 18, 2026

High8.8

Fix: upgrade to 15.8 or later (3 fixed versions below)

A logic issue was addressed with improved checks. This issue is fixed in macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7. An app may be able to break out of its sandbox.

Affected versions

Package	Affected	Fixed in
macOS Product	< 15.8	15.8
	< 26.7	26.7
	< 27	27

Details and references

CVSS 3.1: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Severity from: CISA (its enrichment of the CVE record)
Weakness: CWE-693

More Apple advisories

All Apple

Medium 5.5Sep 14

Apple macOS: path traversalCVE-2026-86902fixed in 14.8.8 +1 Medium 5.5Sep 14

Apple iOS and iPadOS: out-of-bounds readCVE-2026-86903fixed in 27 +2 High 7.5Sep 14

A privacy issue was addressed with improved state managementCVE-2026-86904fixed in 26.7 +2 Medium 5.5Sep 14

Apple iOS and iPadOS: improper access controlCVE-2026-86905fixed in 27 +2 Medium 4.4Sep 14

Apple macOS: protection mechanism failureCVE-2026-86909fixed in 27 Medium 5.5Sep 14

Apple macOS: path traversalCVE-2026-86910fixed in 15.8 +2