Apple watchOS up to 7.3.3 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 identified as problematic has been detected in Apple watchOS up to 7.3.3. This affects an unknown part of the component WebKit. Performing a manipulation results in cross site scripting. This vulnerability is cataloged as CVE-2021-1826. It is possible to initiate the attack remotely. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, was found in Apple watchOS up to 7.3.3 (Smartwatch Operating System). This affects some 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 shared 04/26/2021 as HT212324 as confirmed advisory (Website). It is possible to read the advisory 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. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1059.007 according to MITRE ATT&CK. 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 7.4 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). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

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Version

License

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: watchOS 7.4

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: HT212324
Status: Confirmed

CVE: CVE-2021-1826 (🔍)
GCVE (CVE): GCVE-0-2021-1826
GCVE (VulDB): GCVE-100-174099

Entryinfo

Created: 04/27/2021 11:27
Updated: 07/10/2025 13:15
Changes: 04/27/2021 11:27 (15), 04/27/2021 11:28 (2), 04/27/2021 11:31 (28), 05/01/2021 13:44 (4), 07/10/2025 13:15 (16)
Complete: 🔍
Cache ID: 216::103

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

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