Apple watchOS up to 8.1.1 WebKit out-of-bounds

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 watchOS up to 8.1.1 and classified as critical. This impacts an unknown function of the component WebKit. This manipulation causes out-of-bounds. This vulnerability is tracked as CVE-2021-30953. The attack is possible to be carried out remotely. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability has been found in Apple watchOS up to 8.1.1 (Smartwatch 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 out-of-bounds vulnerability. The CWE definition for the vulnerability is CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability.

The weakness was disclosed 12/13/2021 by VRIJ as HT212975 as confirmed advisory (Website). It is possible to read the advisory at support.apple.com. This vulnerability is known as CVE-2021-30953. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available. The advisory points out:

Processing maliciously crafted web content 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:

An out-of-bounds read was addressed with improved bounds checking.

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: 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: Out-of-bounds
CWE: CWE-125 / 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: VRIJ
Status: Confirmed

CVE: CVE-2021-30953 (🔍)
GCVE (CVE): GCVE-0-2021-30953
GCVE (VulDB): GCVE-100-188527
CERT Bund: WID-SEC-2026-0631 - Apple macOS: Mehrere Schwachstellen

Entryinfo

Created: 12/17/2021 16:07
Updated: 03/07/2026 14:22
Changes: 12/17/2021 16:07 (19), 12/17/2021 16:10 (27), 12/23/2021 07:56 (1), 03/07/2026 14:22 (21)
Complete: 🔍
Cache ID: 216::103

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

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