CVE-2021-1876

Name: CVE-2021-1876
Creator: NVD / NIST
Published: 2021-09-08T15:15:12.207+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.8/10EPSS 1.22%

Last modified Jun 17, 2026

CVE-2021-1876 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. A use after free issue was addressed with improved memory management. This issue is fixed in macOS Big Sur 11.3, Security Update 2021-002 Catalina, Security Update 2021-003 Mojave. EPSS estimates a 1.22% chance of exploitation in the next 30 days.

Description

A use after free issue was addressed with improved memory management. This issue is fixed in macOS Big Sur 11.3, Security Update 2021-002 Catalina, Security Update 2021-003 Mojave. Processing maliciously crafted web content may lead to arbitrary code execution.

Metrics

CVSS 3.1

8.8/10

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

EPSS Probability

1.22%

64.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-416

Affected Software

Vendor	Product	Versions
Apple	Mac Os X	>= 10.14, <= 10.14.5
Apple	Mac Os X	>= 10.15, <= 10.15.5
Apple	Mac Os X	10.14.6
Apple	Mac Os X	10.15.6
Apple	Mac Os X	10.15.7
Apple	Macos	>= 11.0, < 11.3

References

https://support.apple.com/en-us/HT212325Vendor Advisory
https://support.apple.com/en-us/HT212326Vendor Advisory
https://support.apple.com/en-us/HT212327Vendor Advisory
https://support.apple.com/en-us/HT212325Vendor Advisory
https://support.apple.com/en-us/HT212326Vendor Advisory
https://support.apple.com/en-us/HT212327Vendor Advisory

Timeline

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

Frequently Asked Questions

What is CVE-2021-1876?

How severe is CVE-2021-1876?

CVE-2021-1876 has a CVSS score of 8.8/10 (HIGH severity). The EPSS model estimates a 1.22% probability of exploitation in the next 30 days.

How do I fix CVE-2021-1876?

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-2021-1876?

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

Scan your code now

Source: NVD / NIST