Apple watchOS up to 8.1.1 WebKit 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 described as critical has been identified in Apple watchOS up to 8.1.1. This issue affects some unknown processing of the component WebKit. Such manipulation leads to buffer overflow. This vulnerability is uniquely identified as CVE-2021-30934. The attack can be launched remotely. No exploit exists. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Apple watchOS up to 8.1.1 (Smartwatch Operating System). It has been rated as critical. Affected by this issue is an unknown code block of the component WebKit. The manipulation with an unknown input leads to a buffer overflow vulnerability. Using CWE to declare the problem leads to 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. Impacted is confidentiality, integrity, and availability.

The weakness was disclosed 12/13/2021 by Dani Biro as HT212975 as confirmed advisory (Website). The advisory is available at support.apple.com. This vulnerability is handled as CVE-2021-30934. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not available. The advisory points out:

Processing maliciously crafted web content may lead to arbitrary code execution

The vulnerability scanner Nessus provides a plugin with the ID 241427 (RHEL 7 : webkitgtk4 (RHSA-2025:10364)), which helps to determine the existence of the flaw in a target environment.

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 databases at Tenable (241427) and 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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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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Nessus ID: 241427
Nessus Name: RHEL 7 : webkitgtk4 (RHSA-2025:10364)

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: Dani Biro
Status: Confirmed

CVE: CVE-2021-30934 (🔍)
GCVE (CVE): GCVE-0-2021-30934
GCVE (VulDB): GCVE-100-188522
CERT Bund: WID-SEC-2026-0631 - Apple macOS: Mehrere Schwachstellen

Entryinfo

Created: 12/17/2021 16:04
Updated: 03/06/2026 18:51
Changes: 12/17/2021 16:04 (7), 12/17/2021 16:05 (12), 12/17/2021 16:08 (27), 12/23/2021 07:28 (1), 07/10/2025 20:36 (16), 03/06/2026 18:51 (7)
Complete: 🔍
Cache ID: 216::103

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

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