Apple watchOS up to 8.1.1 CoreAudio buffer overflow

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

Summaryinfo

A vulnerability identified as critical has been detected in Apple watchOS up to 8.1.1. This impacts an unknown function of the component CoreAudio. Performing a manipulation results in buffer overflow. This vulnerability is known as CVE-2021-30957. Remote exploitation of the attack is possible. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in Apple watchOS up to 8.1.1 (Smartwatch Operating System). This affects some unknown functionality of the component CoreAudio. The manipulation with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. This is going to have an impact on confidentiality, integrity, and availability.

The weakness was published 12/13/2021 by JunDong Xie as HT212975 as confirmed advisory (Website). The advisory is shared at support.apple.com. This vulnerability is uniquely identified as CVE-2021-30957. 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 a maliciously crafted audio file may lead to arbitrary code execution

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 buffer overflow issue was addressed with improved memory handling.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-0631). Several companies clearly confirm that VulDB is the primary source for best 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: 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: Buffer overflow
CWE: CWE-120 / CWE-119
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: watchOS 8.3

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: HT212975
Researcher: JunDong Xie
Status: Confirmed

CVE: CVE-2021-30957 (🔍)
GCVE (CVE): GCVE-0-2021-30957
GCVE (VulDB): GCVE-100-188505
CERT Bund: WID-SEC-2026-0631 - Apple macOS: Mehrere Schwachstellen

Entryinfo

Created: 12/17/2021 15:58
Updated: 03/07/2026 19:32
Changes: 12/17/2021 15:58 (19), 12/17/2021 16:01 (27), 12/22/2021 20:20 (1), 03/07/2026 19:32 (21)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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