Apple macOS up to 11.3 WebKit memory corruption

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 macOS up to 11.3. The impacted element is an unknown function of the component WebKit. This manipulation causes memory corruption. This vulnerability is registered as CVE-2021-30749. Remote exploitation of the attack is possible. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability has been found in Apple macOS up to 11.3 (Operating System) and classified as critical. Affected by this vulnerability is some unknown functionality of the component WebKit. The manipulation with an unknown input leads to a memory corruption vulnerability. The CWE definition for the vulnerability is CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. As an impact it is known to affect confidentiality, integrity, and availability.

The weakness was published 05/24/2021 as HT212529 as confirmed advisory (Website). The advisory is shared at support.apple.com. This vulnerability is known as CVE-2021-30749. 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 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 11.4 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability. The advisory contains the following remark:

Multiple memory corruption issues were addressed with improved memory handling.

The vulnerability is also documented in the vulnerability database at Tenable (241427). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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: Memory corruption
CWE: 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: 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
Status: Confirmed

CVE: CVE-2021-30749 (🔍)
GCVE (CVE): GCVE-0-2021-30749
GCVE (VulDB): GCVE-100-175765
scip Labs: https://www.scip.ch/en/?labs.20180712

Entryinfo

Created: 05/25/2021 14:35
Updated: 07/10/2025 19:17
Changes: 05/25/2021 14:35 (18), 05/25/2021 14:38 (28), 05/28/2021 16:52 (4), 07/10/2025 19:17 (16)
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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