Out-of-bounds Read in Apple macOS

CVE-2026-20620

An out-of-bounds read issue was addressed with improved input validation. This issue is fixed in macOS Sequoia 15.7.4, macOS Sonoma 14.8.4, macOS Tahoe 26.3. An attacker may be able to cause unexpected system termination or read kernel memory.

Vulnerability class: Buffer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.7 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H.

EPSS exploit prediction

EPSS: 0.002 (9.0th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 9th percentile — 9.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-20620: held from 0.002 to 0.002.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-20620?
CVE-2026-20620 is a high-severity vulnerability in Apple macOS, classified under Out-of-bounds Read. CVSS score: 7.7/10. Published 2026-02-11.
How severe is CVE-2026-20620?
High severity. CVSS v3 base score is 7.7 out of 10.