AppleCVE-2026-84515

Apple macOS: out-of-bounds write

CVE-2026-84515 · Published Sep 14, 2026 · updated Sep 16, 2026

High7.8

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

An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7. Connecting to a malicious SMB server may lead to kernel memory corruption.

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:U/C:H/I:H/A:H
Severity from: CISA (its enrichment of the CVE record)
Weakness: CWE-787

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