Home/CVE/Apple Multiple Products Type Confusion Vulnerability
CVE

CVE-2021-1789

Apple 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.

HIGH · CVSS 8.8 ⚠ CISA KEV EPSS 0.00243
Act now
  • Listed on CISA KEV (known exploited in the wild)
  • SSVC exploitation status: active
  • CVSS base score ≥ 7.0
Sigma rules8 YARA rules0
⬢

Required Remediation

Apply updates per vendor instructions.

⬡

Weakness Classification

CWE-843Access of Resource Using Incompatible Type ('Type Confusion')
CWE-843Access of Resource Using Incompatible Type ('Type Confusion')
▤

Affected Products & Versions

10
apple ipados< 14.4
apple iphone os< 14.4
apple mac os x>= 10.14 and < 10.14.6
apple mac os x>= 10.15 and < 10.15.7
apple mac os xall versions
apple macos>= 11.0 and < 11.2
apple tvos< 14.4
apple watchos< 7.3
◈

Sigma Hunt Rules

8
Exact rules name this CVE ID. Product rules name an affected product in their title. Related rules cover techniques used by actors who exploited this CVE. Showing the most relevant matches; the complete related set is on the full drill-down.
producthighSuspicious Microsoft Office Child Process - MacOS
producthighRemote Access Tool - Renamed MeshAgent Execution - MacOS
producthighBinary Padding - MacOS
productmediumSuspicious Execution via macOS Script Editor
productmediumSystem Information Discovery Via Sysctl - MacOS
productmediumNew File Exclusion Added To Time Machine Via Tmutil - MacOS
▣

Scoring & Timeline

8.8
HIGH · CVSS v3.1 · product-security@apple.com
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD02 Apr 2021 · 06:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
SSVC triage · cisa-vulnrichment
Exploitation
active
Automatable
no
Technical impact
total
SSVC asks the questions that actually drive patch urgency: is it being exploited, can attacks be automated, and how total is the impact.
⚑

Vendor Advisories

9
rhsaRHSA-2025:10364Important
suse-csafopenSUSE-SU-2024:11506-1
cisaKEV-CVE-2021-1789
rhsaRHSA-2021:4381Moderate
suse-csafSUSE-SU-2021:1990-1
🔗

References & Sources

9
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JN6ZOD62CTO54CHTMJTHVEF6R2Y532TJ/Broken LinkMailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L3L6ZZOU5JS7E3RFYGLP7UFLXCG7TNLU/Broken LinkMailing List
https://security.gentoo.org/glsa/202104-03Third Party Advisory
https://support.apple.com/en-us/HT212146Release NotesVendor Advisory
https://support.apple.com/en-us/HT212147Release NotesVendor Advisory
https://support.apple.com/en-us/HT212148Release NotesVendor Advisory
Intelligence Graph · click any node to traverse
CVETechnique ActorTool Family
drag to reposition · click any node to traverse · button top-right enlarges
External lookups - second-class, for what we don’t hold ourselves
NVDCVE.orgCISAVulnersExploit-DBGitHub PoCVulnCheck KEVGreyNoise
Vulnerabilities
CISA KEV catalog
CWE weaknesses
CAPEC attack patterns
Package vulnerabilities
Threat intelligence
Threat actors
Tools & malware
ATT&CK techniques
IOCs
Detection & defense
Sigma rules
YARA rules
Atomic Red Team tests
D3FEND countermeasures
Compliance
NIST 800-53
ISO 27001:2022
SOC 2 TSC
PCI-DSS v4.0
CIS Controls v8.1
About
All capabilities
Live statistics
Data sources
Privacy policy
Terms of service
threatengine.sh  ·  Open-source threat intelligence platform  ·  100+ authoritative sources  ·  Every fact traces to its origin