What is CVE-2018-4456?

CVE-2018-4456 is a high-severity vulnerability in Apple Mac OS X, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 7.8/10. Published 2019-04-03.

How severe is CVE-2018-4456?

High severity. CVSS v3 base score is 7.8 out of 10.

Buffer overflow in Apple Mac OS X

CVE-2018-4456

A memory corruption issue was addressed with improved input validation. This issue affected versions prior to macOS High Sierra 10.13.6, macOS Mojave 10.14.

Vulnerability class: Buffer Overflow

Published 2019-04-03 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.011 (64.7th percentile), scored 2026-10-02.

Low probability of exploitation in the next 30 days, but still tracked. 65th percentile — 64.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.011 · newest: 0.011 · change: 0.000

Affected products

Apple Mac OS X
macOS — versions Versions prior to: macOS High Sierra 10.13.6, macOS Mojave 10.14

Weakness classification (CWE)

CWE-119 — Improper Restriction of Operations within the Bounds of a Memory Buffer

References

support.apple.com/kb/HT209139 (Vendor Advisory)
support.apple.com/kb/HT208937 (Vendor Advisory)
support.apple.com/kb/HT209341 (Vendor Advisory)
seclists.org/fulldisclosure/2019/May/20 (mailing-list)
support.apple.com/kb/HT210119
seclists.org/bugtraq/2019/May/27 (mailing-list)

Frequently asked questions

What is CVE-2018-4456?: CVE-2018-4456 is a high-severity vulnerability in Apple Mac OS X, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 7.8/10. Published 2019-04-03.
How severe is CVE-2018-4456?: High severity. CVSS v3 base score is 7.8 out of 10.