What is CVE-2026-64767?

CVE-2026-64767 is a critical-severity vulnerability in Apple macOS, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.8/10. Published 2026-07-27.

How severe is CVE-2026-64767?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Buffer overflow in Apple macOS

CVE-2026-64767

A buffer overflow was addressed with improved bounds checking. This issue is fixed in macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.6. A remote attacker may be able to cause unexpected system termination or corrupt kernel memory.

Vulnerability class: Buffer Overflow

EPSS: 0.007 (50.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Apple Macos — versions 0

Weakness classification (CWE)

CWE-120 — Buffer Copy without Checking Size of Input (Classic Buffer Overflow)

References

product-security@apple.com (Release Notes, Vendor Advisory)
product-security@apple.com (Release Notes, Vendor Advisory)
product-security@apple.com (Release Notes, Vendor Advisory)

Frequently asked questions

What is CVE-2026-64767?: CVE-2026-64767 is a critical-severity vulnerability in Apple macOS, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.8/10. Published 2026-07-27.
How severe is CVE-2026-64767?: Critical severity. CVSS v3 base score is 9.8 out of 10.