Apple tvOS up to 14.4 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 classified as problematic has been found in Apple tvOS up to 14.4. This affects an unknown function of the component WebKit. This manipulation causes cross site scripting. This vulnerability is handled as CVE-2021-1826. The attack can be initiated remotely. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic was found in Apple tvOS up to 14.4 (Digital Media Player). Affected by this vulnerability is some unknown processing of the component WebKit. The manipulation with an unknown input leads to a cross site scripting vulnerability. The CWE definition for the vulnerability is 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. As an impact it is known to affect integrity.

The weakness was released 04/26/2021 as HT212323 as confirmed advisory (Website). The advisory is shared at support.apple.com. This vulnerability is known 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 14.5 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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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: tvOS 14.5

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: HT212323
Status: Confirmed

CVE: CVE-2021-1826 (🔍)
GCVE (CVE): GCVE-0-2021-1826
GCVE (VulDB): GCVE-100-174061

Entryinfo

Created: 04/27/2021 10:59
Updated: 07/10/2025 13:15
Changes: 04/27/2021 10:59 (17), 04/27/2021 11:02 (28), 05/01/2021 10:05 (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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