Apple macOS up to 11.1 WebKit Remote Code Execution

CVSS Meta Temp Score
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CTI Interest Score
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8.5$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in Apple macOS up to 11.1. Impacted is an unknown function of the component WebKit. Performing a manipulation results in an unknown weakness. This vulnerability is cataloged as CVE-2021-1871. It is possible to initiate the attack remotely. Furthermore, there is an exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in Apple macOS up to 11.1 (Operating System). This affects some unknown processing of the component WebKit. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

A logic issue was addressed with improved restrictions. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, iOS 14.4 and iPadOS 14.4. A remote attacker may be able to cause arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited..

The weakness was shared 02/01/2021 as HT212147 as confirmed advisory (Website). It is possible to read the advisory at support.apple.com. This vulnerability is uniquely identified as CVE-2021-1871. It demands that the victim is doing some kind of user interaction. Technical details are unknown but an exploit is available. The advisory points out:

A remote attacker may be able to cause arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited.

It is declared as attacked. 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. The CISA Known Exploited Vulnerabilities Catalog lists this issue since 11/03/2021 with a due date of 11/17/2021:

Apply updates per vendor instructions.

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 logic issue was addressed with improved restrictions.

The vulnerability is also documented in the databases at Zero-Day.cz (601), Tenable (241427) and EUVD (EUVD-2021-7335). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.6
VulDB Meta Temp Score: 8.5

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔍

CNA Base Score: 9.8
CNA Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Remote Code Execution
CWE: Unknown
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Attacked

EPSS Score: 🔍
EPSS Percentile: 🔍

KEV Added: 🔍
KEV Due: 🔍
KEV Remediation: 🔍
KEV Ransomware: 🔍
KEV Notice: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 241427
Nessus Name: RHEL 7 : webkitgtk4 (RHSA-2025:10364)

Zero-Day.cz: 🔍

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 🔍
07/29/2025 +1637 days 🔍

Sourcesinfo

Vendor: apple.com

Advisory: HT212147
Status: Confirmed

CVE: CVE-2021-1871 (🔍)
GCVE (CVE): GCVE-0-2021-1871
GCVE (VulDB): GCVE-100-169119
EUVD: 🔍
scip Labs: https://www.scip.ch/en/?labs.20180712

Entryinfo

Created: 02/03/2021 14:14
Updated: 07/29/2025 06:02
Changes: 02/03/2021 14:14 (12), 02/03/2021 14:15 (5), 02/03/2021 14:18 (29), 02/23/2021 08:49 (1), 04/20/2024 13:26 (28), 05/15/2024 17:15 (2), 06/30/2024 11:30 (2), 07/26/2024 22:35 (20), 09/11/2024 11:01 (1), 01/30/2025 00:15 (11), 05/04/2025 06:18 (3), 07/10/2025 09:44 (2), 07/29/2025 06:02 (1)
Complete: 🔍
Cache ID: 216::103

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