CVE-2021-1871

CriticalCVSS 9.8/10Known exploited (CISA KEV)Last modified Jun 17, 2026

Description

A logic issue was addressed with improved restrictions. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, iOS 14.4 and iPadOS 14.4. A remote attacker may be able to cause arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited..

Metrics

CVSS 3.1 9.8/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected software

No affected versions have been published.

Timeline

Published
Apr 2, 2021
Last modified
Jun 17, 2026
Added to CISA KEV
Nov 3, 2021
NVD status
Analyzed

Related CVEs from 2021

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CVE-2021-1871: Critical severity, CVSS 9.8 | Vulnix