Apple macOS up to 12.0 WebKit type confusion

CVSS Meta Temp Score
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CTI Interest Score
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6.0$0-$5k0.00

Summaryinfo

A vulnerability has been found in Apple macOS up to 12.0 and classified as critical. This vulnerability affects unknown code of the component WebKit. This manipulation causes type confusion. This vulnerability appears as CVE-2021-30954. The attack may be initiated remotely. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability has been found in Apple macOS up to 12.0 (Operating System) and classified as critical. Affected by this vulnerability is an unknown part of the component WebKit. The manipulation with an unknown input leads to a type confusion vulnerability. The CWE definition for the vulnerability is CWE-843. The product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type. As an impact it is known to affect confidentiality, integrity, and availability.

The weakness was presented 12/13/2021 with Kunlun Lab as HT212978 as confirmed advisory (Website). The advisory is shared at support.apple.com. This vulnerability is known as CVE-2021-30954. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. The advisory points out:

Processing maliciously crafted web content may lead to arbitrary code execution

Upgrading to version 12.1 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability. The advisory contains the following remark:

A type confusion issue was addressed with improved memory handling.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-0631). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

  • Apple macOS

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Type confusion
CWE: CWE-843
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Upgrade: macOS 12.1

Timelineinfo

04/13/2021 🔍
12/13/2021 +244 days 🔍
12/13/2021 +0 days 🔍
12/17/2021 +4 days 🔍
03/07/2026 +1541 days 🔍

Sourcesinfo

Vendor: apple.com

Advisory: HT212978
Organization: Kunlun Lab
Status: Confirmed

CVE: CVE-2021-30954 (🔍)
GCVE (CVE): GCVE-0-2021-30954
GCVE (VulDB): GCVE-100-188653
CERT Bund: WID-SEC-2026-0631 - Apple macOS: Mehrere Schwachstellen

scip Labs: https://www.scip.ch/en/?labs.20180712

Entryinfo

Created: 12/17/2021 21:25
Updated: 03/07/2026 19:32
Changes: 12/17/2021 21:25 (10), 12/17/2021 21:26 (9), 12/17/2021 21:29 (28), 12/24/2021 07:34 (1), 03/07/2026 19:32 (21)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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