What is CVE-2019-8555?

CVE-2019-8555 is a high-severity vulnerability in Apple macOS, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 7.8/10. Published 2019-12-18.

How severe is CVE-2019-8555?

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

Buffer overflow in Apple macOS

CVE-2019-8555

A buffer overflow was addressed with improved size validation. This issue is fixed in macOS Mojave 10.14.4. A malicious application may be able to execute arbitrary code with kernel privileges.

Vulnerability class: Buffer Overflow

Published 2019-12-18 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.013 (70.2th percentile), scored 2026-10-02.

Low probability of exploitation in the next 30 days, but still tracked. 70th percentile — 70.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.013 · newest: 0.013 · change: 0.000

Affected products

Apple macOS — versions unspecified
Apple Mac OS X

Weakness classification (CWE)

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

References

support.apple.com/HT209600 (Vendor Advisory)

Frequently asked questions

What is CVE-2019-8555?: CVE-2019-8555 is a high-severity vulnerability in Apple macOS, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 7.8/10. Published 2019-12-18.
How severe is CVE-2019-8555?: High severity. CVSS v3 base score is 7.8 out of 10.