Apple Safari up to 14.0 WebKit memory corruption

Summaryinfo

A vulnerability was found in Apple Safari up to 14.0. It has been declared as critical. Affected by this issue is some unknown functionality of the component WebKit. The manipulation results in memory corruption. This vulnerability is identified as CVE-2021-30665. The attack can be executed remotely. Additionally, an exploit exists. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Apple Safari up to 14.0 (Web Browser). It has been classified as critical. Affected is some unknown processing of the component WebKit. The manipulation with an unknown input leads to a memory corruption vulnerability. CWE is classifying the issue as 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. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

A memory corruption issue was addressed with improved state management. This issue is fixed in watchOS 7.4.1, iOS 14.5.1 and iPadOS 14.5.1, tvOS 14.6, iOS 12.5.3, macOS Big Sur 11.3.1. Processing maliciously crafted web content may lead to arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited..

The weakness was released 05/04/2021 by yangkang as HT212340 as confirmed advisory (Website). The advisory is shared for download at support.apple.com. This vulnerability is traded as CVE-2021-30665. Successful exploitation requires user interaction by the victim. Technical details are unknown but a private exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 07/29/2025). The advisory points out:

Processing maliciously crafted web content may lead to 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. This issue was added on 11/03/2021 to the CISA Known Exploited Vulnerabilities Catalog with a due date of 11/17/2021:

Apply updates per vendor instructions.

Upgrading to version 14.1 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 databases at Zero-Day.cz (625), Tenable (241427) and EUVD (EUVD-2021-17582). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Web Browser

Vendor

• Apple

Name

• Safari

Version

• 14.0

License

• commercial

Website

• Vendor: https://www.apple.com/

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Duplicate

• Submit #XXXXX: Xxx-xxxx-xxxxx, Xxx-xxxx-xxxxx // Xxxx Xxxxxxxxx Xx Xxxxx Xxxxxx < Xx.x (by CSieberg)

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