Apple macOS up to 11.2.3 WebKit cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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4.1$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, has been found in Apple macOS up to 11.2.3. Affected by this issue is some unknown functionality of the component WebKit. Performing a manipulation results in cross site scripting. This vulnerability is identified as CVE-2021-1826. The attack can be initiated remotely. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in Apple macOS up to 11.2.3 (Operating System). It has been classified as problematic. This affects an unknown functionality of the component WebKit. The manipulation with an unknown input leads to a cross site scripting vulnerability. CWE is classifying the issue as CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. This is going to have an impact on integrity.

The weakness was released 04/26/2021 as HT212325 as confirmed advisory (Website). The advisory is shared at support.apple.com. This vulnerability is uniquely identified as CVE-2021-1826. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1059.007 for this issue. The advisory points out:

Processing maliciously crafted web content may lead to universal cross site scripting

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 logic issue was addressed with improved restrictions.

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

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Vendor

Name

Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.1

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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

Exploitinginfo

Class: Cross site scripting
CWE: CWE-79 / CWE-94 / CWE-74
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-2021-1826 (🔍)
GCVE (CVE): GCVE-0-2021-1826
GCVE (VulDB): GCVE-100-174021
scip Labs: https://www.scip.ch/en/?labs.20180712

Entryinfo

Created: 04/27/2021 09:51
Updated: 07/10/2025 13:15
Changes: 04/27/2021 09:51 (17), 04/27/2021 09:54 (29), 05/01/2021 08:16 (4), 07/10/2025 13:15 (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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