What is CVE-2020-9945?

CVE-2020-9945 is a medium-severity vulnerability in Apple macOS, classified under Improper Restriction of Rendered UI Layers or Frames (Clickjacking). CVSS score: 4.3/10. Published 2020-12-08.

How severe is CVE-2020-9945?

Medium severity. CVSS v3 base score is 4.3 out of 10.

Vulnerability in Apple macOS

CVE-2020-9945

A spoofing issue existed in the handling of URLs. This issue was addressed with improved input validation. This issue is fixed in macOS Big Sur 11.0.1, Safari 14.0.1. Visiting a malicious website may lead to address bar spoofing.

Published 2020-12-08 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N.

EPSS exploit prediction

EPSS: 0.012 (66.5th percentile), scored 2026-10-01.

Low probability of exploitation in the next 30 days, but still tracked. 66th percentile — 66.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.012 · newest: 0.012 · change: +0.000

Affected products

Apple macOS — versions unspecified
Apple Mac OS X
Apple Safari

Weakness classification (CWE)

CWE-1021 — Improper Restriction of Rendered UI Layers or Frames (Clickjacking)

References

support.apple.com/en-us/HT211931 (Release Notes, Vendor Advisory)
support.apple.com/en-us/HT211934 (Release Notes, Vendor Advisory)
seclists.org/fulldisclosure/2020/Dec/32 (mailing-list, Mailing List, Third Party Advisory)

Frequently asked questions

What is CVE-2020-9945?: CVE-2020-9945 is a medium-severity vulnerability in Apple macOS, classified under Improper Restriction of Rendered UI Layers or Frames (Clickjacking). CVSS score: 4.3/10. Published 2020-12-08.
How severe is CVE-2020-9945?: Medium severity. CVSS v3 base score is 4.3 out of 10.