Apple macOS up to 11.2.3 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 classified as critical was found in Apple macOS up to 11.2.3. Affected by this vulnerability is an unknown functionality of the component WebKit. Such manipulation leads to memory corruption. This vulnerability is referenced as CVE-2021-1817. It is possible to launch the attack remotely. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Apple macOS up to 11.2.3 (Operating System) and classified as critical. Affected by this issue is an unknown function of the component WebKit. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to 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. Impacted is confidentiality, integrity, and availability.

The weakness was published 04/26/2021 as HT212325 as confirmed advisory (Website). The advisory is shared for download at support.apple.com. This vulnerability is handled as CVE-2021-1817. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit 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 11.3 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability. The advisory contains the following remark:

A memory corruption issue was addressed with improved state management.

The vulnerability is also documented in the vulnerability database at Tenable (241427). Once again VulDB remains the best 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: 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 11.3

Timelineinfo

12/08/2020 🔍
04/26/2021 +138 days 🔍
04/26/2021 +0 days 🔍
04/27/2021 +1 days 🔍
07/10/2025 +1535 days 🔍

Sourcesinfo

Vendor: apple.com

Advisory: HT212325
Status: Confirmed

CVE: CVE-2021-1817 (🔍)
GCVE (CVE): GCVE-0-2021-1817
GCVE (VulDB): GCVE-100-174020
scip Labs: https://www.scip.ch/en/?labs.20180712

Entryinfo

Created: 04/27/2021 09:50
Updated: 07/10/2025 09:44
Changes: 04/27/2021 09:50 (16), 04/27/2021 09:51 (2), 04/27/2021 09:54 (28), 05/01/2021 08:12 (4), 07/10/2025 09:44 (16)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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