Apple Safari up to 15.0 WebKit type confusion

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$0-$5k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in Apple Safari up to 15.0. The impacted element is an unknown function of the component WebKit. Executing a manipulation can lead to type confusion. This vulnerability is tracked as CVE-2021-30954. The attack can be launched remotely. No exploit exists. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in Apple Safari up to 15.0 (Web Browser). It has been declared as critical. This vulnerability affects an unknown functionality 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 disclosed 12/14/2021 with Kunlun Lab as HT212982 as confirmed advisory (Website). The advisory is available at support.apple.com. This vulnerability was named CVE-2021-30954. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 03/07/2026). The advisory points out:

Processing maliciously crafted web content may lead to arbitrary code execution

Upgrading to version 15.2 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 best quality of vulnerability data, you may have to visit 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: Safari 15.2

Timelineinfo

04/13/2021 🔍
12/14/2021 +245 days 🔍
12/14/2021 +0 days 🔍
12/17/2021 +3 days 🔍
03/07/2026 +1541 days 🔍

Sourcesinfo

Vendor: apple.com

Advisory: HT212982
Organization: Kunlun Lab
Status: Confirmed

CVE: CVE-2021-30954 (🔍)
GCVE (CVE): GCVE-0-2021-30954
GCVE (VulDB): GCVE-100-188602
CERT Bund: WID-SEC-2026-0631 - Apple macOS: Mehrere Schwachstellen

Entryinfo

Created: 12/17/2021 16:59
Updated: 03/07/2026 14:22
Changes: 12/17/2021 16:59 (3), 12/17/2021 17:00 (16), 12/17/2021 17:03 (27), 12/23/2021 13:21 (1), 03/07/2026 14:22 (21)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Discussion

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