What is CVE-2019-8858?

CVE-2019-8858 is a medium-severity vulnerability in Apple macOS. CVSS score: 5.3/10. Published 2020-10-27.

How severe is CVE-2019-8858?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Vulnerability in Apple macOS

CVE-2019-8858

A logic issue was addressed with improved state management. This issue is fixed in macOS Catalina 10.15.1, Security Update 2019-001, and Security Update 2019-006. A user who shares their screen may not be able to end screen sharing.

Published 2020-10-27 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.

EPSS exploit prediction

EPSS: 0.007 (51.7th percentile), scored 2026-10-02.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 52nd percentile — 51.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: 0.000

Affected products

Apple macOS — versions unspecified
Apple Mac OS X

References

support.apple.com/en-us/HT210722 (Release Notes, Vendor Advisory)

Frequently asked questions

What is CVE-2019-8858?: CVE-2019-8858 is a medium-severity vulnerability in Apple macOS. CVSS score: 5.3/10. Published 2020-10-27.
How severe is CVE-2019-8858?: Medium severity. CVSS v3 base score is 5.3 out of 10.