AppleCVE-2026-64691

Apple macOS: buffer overflow

CVE-2026-64691 · Published Jul 27, 2026 · updated Jul 28, 2026

Critical9.8

Fix: upgrade to 26.6 or later

A buffer overflow was addressed with improved size validation. This issue is fixed in macOS Tahoe 26.6. An app may be able to cause unexpected system termination.

Affected versions

Package	Affected	Fixed in
macOS Product	< 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-120

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