Apple watchOS up to 7.3.3 WebKit memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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6.0$0-$5k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in Apple watchOS up to 7.3.3. Affected by this issue is some unknown functionality of the component WebKit. Such manipulation leads to memory corruption. This vulnerability is listed as CVE-2021-1817. The attack may be performed from remote. There is no available exploit. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Apple watchOS up to 7.3.3 (Smartwatch Operating System). Affected by this issue is an unknown functionality of the component WebKit. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. Impacted is confidentiality, integrity, and availability.

The weakness was presented 04/26/2021 as HT212324 as confirmed advisory (Website). The advisory is available at support.apple.com. This vulnerability is handled as CVE-2021-1817. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not 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 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 memory corruption issue was addressed with improved state management.

The vulnerability is also documented in the vulnerability database at Tenable (241427). If you want to get best quality of vulnerability data, you may have to visit VulDB.

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: Memory corruption
CWE: 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: 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-2021-1817 (🔍)
GCVE (CVE): GCVE-0-2021-1817
GCVE (VulDB): GCVE-100-174098

Entryinfo

Created: 04/27/2021 11:27
Updated: 07/10/2025 09:44
Changes: 04/27/2021 11:27 (18), 04/27/2021 11:30 (27), 05/01/2021 13:38 (4), 07/10/2025 09:44 (16)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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