CVE-2021-1789

HighCVSS 8.8/10Known exploited (CISA KEV)Last modified Jun 17, 2026

Description

A type confusion issue was addressed with improved state handling. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, tvOS 14.4, watchOS 7.3, iOS 14.4 and iPadOS 14.4, Safari 14.0.3. Processing maliciously crafted web content may lead to arbitrary code execution.

Metrics

CVSS 3.1 8.8/10CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Weakness enumeration

CWE-843

Affected software

VendorProductVersions
AppleiOS and iPadOS>= unspecified, < 14.4
ApplemacOS>= unspecified, < 11.2
ApplemacOS>= unspecified, < 7.3
ApplemacOS>= unspecified, < 14.4
ApplemacOS>= unspecified, < 14.0

References

Timeline

Published
Apr 2, 2021
Last modified
Jun 17, 2026
Added to CISA KEV
May 4, 2022
NVD status
Analyzed

Related CVEs from 2021

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CVE-2021-1789: High severity, CVSS 8.8 | Vulnix