Out-of-bounds Read in Apple macOS

CVE-2026-86900

An out-of-bounds read issue was addressed with improved input validation. This issue is fixed in macOS Golden Gate 27. Mounting a maliciously crafted exFAT volume may cause unexpected system termination or kernel memory disclosure.

Vulnerability class: Buffer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.003 (27.8th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 28th percentile — 27.8% 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-2026-86900: held from 0.003 to 0.003.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-86900?
CVE-2026-86900 is a medium-severity vulnerability in Apple macOS, classified under Out-of-bounds Read. CVSS score: 6.5/10. Published 2026-09-14.
How severe is CVE-2026-86900?
Medium severity. CVSS v3 base score is 6.5 out of 10.