CVE-2021-30821

Name: CVE-2021-30821
Creator: NVD / NIST
Published: 2021-10-28T19:15:09.047+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.8/10EPSS 1.04%

Last modified Jun 17, 2026

CVE-2021-30821 is a high-severity vulnerability rated 7.8/10 on the CVSS scale. A memory corruption issue was addressed with improved memory handling. This issue is fixed in macOS Monterey 12.0.1, Security Update 2021-007 Catalina, macOS Big Sur 11.6.1. EPSS estimates a 1.04% chance of exploitation in the next 30 days.

Description

A memory corruption issue was addressed with improved memory handling. This issue is fixed in macOS Monterey 12.0.1, Security Update 2021-007 Catalina, macOS Big Sur 11.6.1. A malicious application may be able to execute arbitrary code with kernel privileges.

Metrics

CVSS 3.1

7.8/10

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

EPSS Probability

1.04%

59.6th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

Vendor	Product	Versions
Apple	Mac Os X	< 10.15.7
Apple	Mac Os X	10.15.7
Apple	Macos	>= 11.0, < 11.6.1
Apple	Macos	>= 12.0.0, < 12.0.1

References

https://support.apple.com/en-us/HT212869Vendor Advisory
https://support.apple.com/en-us/HT212871Vendor Advisory
https://support.apple.com/en-us/HT212872Vendor Advisory
https://support.apple.com/en-us/HT212869Vendor Advisory
https://support.apple.com/en-us/HT212871Vendor Advisory
https://support.apple.com/en-us/HT212872Vendor Advisory

Timeline

Published: Oct 28, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-30821?

How severe is CVE-2021-30821?

CVE-2021-30821 has a CVSS score of 7.8/10 (HIGH severity). The EPSS model estimates a 1.04% probability of exploitation in the next 30 days.

How do I fix CVE-2021-30821?

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-2021-30821?

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

Scan your code now

Source: NVD / NIST