Apple macOS up to 11.1 WebKit use after free

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 11.1. Affected by this issue is some unknown functionality of the component WebKit. The manipulation leads to use after free. This vulnerability is referenced as CVE-2021-1788. Remote exploitation of the attack is possible. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Apple macOS up to 11.1 (Operating System) and classified as critical. This issue affects some unknown functionality of the component WebKit. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability.

The weakness was published 02/01/2021 by Francisco Alonso as HT212147 as confirmed advisory (Website). It is possible to read the advisory at support.apple.com. The identification of this vulnerability is CVE-2021-1788. 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

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

A use after free issue was addressed with improved memory management.

The vulnerability is also documented in the vulnerability database at Tenable (241427). Statistical analysis made it clear that VulDB provides the best quality 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: Use after free
CWE: CWE-416 / 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 11.2

Timelineinfo

12/08/2020 🔍
02/01/2021 +55 days 🔍
02/01/2021 +0 days 🔍
02/03/2021 +2 days 🔍
07/10/2025 +1618 days 🔍

Sourcesinfo

Vendor: apple.com

Advisory: HT212147
Researcher: Francisco Alonso
Status: Confirmed

CVE: CVE-2021-1788 (🔍)
GCVE (CVE): GCVE-0-2021-1788
GCVE (VulDB): GCVE-100-169115
scip Labs: https://www.scip.ch/en/?labs.20180712

Entryinfo

Created: 02/03/2021 14:12
Updated: 07/10/2025 09:44
Changes: 02/03/2021 14:12 (19), 02/03/2021 14:16 (28), 02/23/2021 08:31 (4), 07/10/2025 09:44 (16)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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