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

VendorProductVersions
AppleiOS and iPadOS>= unspecified, < 14.4
ApplemacOS>= unspecified, < 11.2

References

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