CVE-2021-1789Apple Multiple Products Type Confusion Vulnerability

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.

8.8 HIGHEPSS 13.97%⚡ Known Exploited (CISA KEV)NVD: Analyzed

Last updated: 2026-06-17 03:32 UTC

OverviewCVSS details

8.8HIGHCVSS 3.1

Score source: NVD
NVD status: Analyzed
Published: Apr 2, 2021
Assigner: apple

Affected

iOS and iPadOS (Apple)

Versions: before 14.4
Fixed in: 14.4

+4 more products →

Exploitation

Public exploit: None listed
CISA KEV: Listed · May 4, 2022
KEV due date: May 25, 2022
Ransomware use: Unknown
SSVC: Exploitation active · Automatable no · Impact total

EPSS · FIRST, scored Nov 7

13.97%chance of exploitation in 30 days

Higher than 96.57% of CVEs

CVSS 3.1 · NVD

8.8High

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

Attack vector: Network
Attack complexity: Low
Privileges required: None
User interaction: Required
Scope: Unchanged
Confidentiality impact: High
Integrity impact: High
Availability impact: High

CVSS 2.0 · NVD

6.8Medium

AV:N/AC:M/Au:N/C:P/I:P/A:P

Attack vector: Network
Attack complexity: Medium
Authentication: None
Confidentiality impact: Partial
Integrity impact: Partial
Availability impact: Partial

NVD status: Analyzed

Overview Affected Products References

NVD CVE.org

Overview

Severity

Score	Severity	Version	Vector String
8.8	HIGH	3.1NVD	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
6.8	MEDIUM	2.0NVD	AV:N/AC:M/Au:N/C:P/I:P/A:P

CISA required action

⚡ Known exploited · remediation due May 25, 2022

Apply updates per vendor instructions.

Details

CVE ID: CVE-2021-1789
Status: Analyzed
Assigner (CNA): apple
Published: Apr 2, 2021
Last modified: 2026-06-17 03:32 UTC
Weaknesses: CWE-843

Sources

Refreshed hourly from the sources above. Last fetched 2026-11-08 13:47 UTC.