Apple macOS up to 12.0 Kernel race condition

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

Summaryinfo

A vulnerability was found in Apple macOS up to 12.0. It has been rated as critical. Affected by this issue is some unknown functionality of the component Kernel. This manipulation causes race condition. The identification of this vulnerability is CVE-2021-30955. The attack can only be executed locally. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Apple macOS up to 12.0 (Operating System). It has been declared as critical. Affected by this vulnerability is an unknown function of the component Kernel. The manipulation with an unknown input leads to a race condition vulnerability. The CWE definition for the vulnerability is CWE-362. The product contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently. As an impact it is known to affect confidentiality, integrity, and availability.

The weakness was shared 12/13/2021 by Zweig as HT212978 as confirmed advisory (Website). The advisory is shared at support.apple.com. This vulnerability is known as CVE-2021-30955. Neither technical details nor an exploit are publicly available. The advisory points out:

A malicious application may be able to execute arbitrary code with kernel privileges

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 race condition was addressed with improved state 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: 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: Race condition
CWE: CWE-362
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: 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
Researcher: Zweig
Status: Confirmed

CVE: CVE-2021-30955 (🔍)
GCVE (CVE): GCVE-0-2021-30955
GCVE (VulDB): GCVE-100-188629
CERT Bund: WID-SEC-2026-0631 - Apple macOS: Mehrere Schwachstellen

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

Entryinfo

Created: 12/17/2021 21:16
Updated: 03/07/2026 19:32
Changes: 12/17/2021 21:16 (19), 12/17/2021 21:20 (28), 12/23/2021 15:32 (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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