Apple watchOS up to 8.1.1 Kernel use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.5$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, has been found in Apple watchOS up to 8.1.1. This issue affects some unknown processing of the component Kernel. Performing a manipulation results in use after free. This vulnerability is identified as CVE-2021-30927. The attack is only possible with local access. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in Apple watchOS up to 8.1.1 (Smartwatch Operating System). It has been classified as critical. This affects an unknown functionality of the component Kernel. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability.

The weakness was released 12/13/2021 by Xinru Chi as HT212975 as confirmed advisory (Website). It is possible to read the advisory at support.apple.com. This vulnerability is uniquely identified as CVE-2021-30927. The technical details are unknown and an exploit is not publicly available. The advisory points out:

An application may be able to execute arbitrary code with kernel privileges

Upgrading to version 8.3 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability. The advisory contains the following remark:

A use after free issue was addressed with improved memory management.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-0631). Be aware that VulDB is the high quality source for vulnerability data.

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: 7.8
VulDB Meta Temp Score: 7.5

VulDB Base Score: 7.8
VulDB Temp Score: 7.5
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: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

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: watchOS 8.3

Timelineinfo

04/13/2021 🔍
12/13/2021 +244 days 🔍
12/13/2021 +0 days 🔍
12/17/2021 +4 days 🔍
03/06/2026 +1540 days 🔍

Sourcesinfo

Vendor: apple.com

Advisory: HT212975
Researcher: Xinru Chi
Status: Confirmed

CVE: CVE-2021-30927 (🔍)
GCVE (CVE): GCVE-0-2021-30927
GCVE (VulDB): GCVE-100-188511
CERT Bund: WID-SEC-2026-0631 - Apple macOS: Mehrere Schwachstellen

Entryinfo

Created: 12/17/2021 16:00
Updated: 03/06/2026 18:44
Changes: 12/17/2021 16:00 (19), 12/17/2021 16:03 (27), 12/22/2021 21:22 (1), 03/06/2026 18:44 (21)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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