CVE-2021-30668

Name: CVE-2021-30668
Creator: NVD / NIST
Published: 2021-09-08T15:15:13.643+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 4.6/10EPSS 0.26%

Last modified Jun 17, 2026

CVE-2021-30668 is a medium-severity vulnerability rated 4.6/10 on the CVSS scale. This issue was addressed with improved checks. This issue is fixed in macOS Big Sur 11.4. EPSS estimates a 0.26% chance of exploitation in the next 30 days.

Description

This issue was addressed with improved checks. This issue is fixed in macOS Big Sur 11.4. A person with physical access to a Mac may be able to bypass Login Window during a software update.

Metrics

CVSS 3.1

4.6/10

CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

EPSS Probability

0.26%

17.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-287

Affected Software

Vendor	Product	Versions
Apple	Macos	< 11.4

References

https://support.apple.com/en-us/HT212529Release Notes, Vendor Advisory
https://support.apple.com/en-us/HT212529Release Notes, Vendor Advisory

Timeline

Published: Sep 8, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-30668?

This issue was addressed with improved checks. This issue is fixed in macOS Big Sur 11.4. A person with physical access to a Mac may be able to bypass Login Window during a software update.

How severe is CVE-2021-30668?

CVE-2021-30668 has a CVSS score of 4.6/10 (MEDIUM severity). The EPSS model estimates a 0.26% probability of exploitation in the next 30 days.

How do I fix CVE-2021-30668?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-30668?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST