Apple macOS up to 11.3 WebKit Remote Code Execution

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

Summaryinfo

A vulnerability marked as critical has been reported in Apple macOS up to 11.3. This impacts an unknown function of the component WebKit. Performing a manipulation results in an unknown weakness. This vulnerability is reported as CVE-2021-30720. The attack is possible to be carried out remotely. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Apple macOS up to 11.3 (Operating System). It has been classified as critical. This affects an unknown code of the component WebKit. This is going to have an impact on confidentiality.

The weakness was disclosed 05/24/2021 by David Schütz as HT212529 as confirmed advisory (Website). It is possible to read the advisory at support.apple.com. This vulnerability is uniquely identified as CVE-2021-30720. 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:

A malicious website may be able to access restricted ports on arbitrary servers

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

A logic issue was addressed with improved restrictions.

The vulnerability is also documented in the vulnerability database at Tenable (241427). Be aware that VulDB is the high quality source for vulnerability data.

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: Remote Code Execution
CWE: Unknown
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: macOS 11.4

Timelineinfo

04/13/2021 🔍
05/24/2021 +41 days 🔍
05/24/2021 +0 days 🔍
05/25/2021 +1 days 🔍
07/10/2025 +1507 days 🔍

Sourcesinfo

Vendor: apple.com

Advisory: HT212529
Researcher: David Schütz
Status: Confirmed

CVE: CVE-2021-30720 (🔍)
GCVE (CVE): GCVE-0-2021-30720
GCVE (VulDB): GCVE-100-175767
scip Labs: https://www.scip.ch/en/?labs.20180712

Entryinfo

Created: 05/25/2021 14:36
Updated: 07/10/2025 19:17
Changes: 05/25/2021 14:36 (18), 05/25/2021 14:39 (28), 05/28/2021 17:07 (4), 07/10/2025 19:17 (17)
Complete: 🔍
Cache ID: 216::103

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

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