AppleCVE-2026-39873

Apple macOS: memory corruption

CVE-2026-39873 · Published Jul 27, 2026 · updated Jul 28, 2026

Critical9.8

Fix: upgrade to 14.8.8 or later (3 fixed versions below)

The issue was addressed with improved memory handling. This issue is fixed in macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.6. Connecting to a malicious SMB server may lead to unexpected system termination.

Affected versions

Package	Affected	Fixed in
macOS Product	< 14.8.8	14.8.8
	< 15.7.8	15.7.8
	< 26.6	26.6

Details and references

CVSS 3.1: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity from: CISA (its enrichment of the CVE record)
Weakness: CWE-119

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