Apple Safari up to 13.1.2 WebKit use after free

Summaryinfo

A vulnerability was found in Apple Safari up to 13.1.2. It has been rated as critical. Affected by this issue is some unknown functionality of the component WebKit. This manipulation causes use after free. This vulnerability is handled as CVE-2020-9951. The attack can be initiated remotely. There is not any exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as critical was found in Apple Safari up to 13.1.2 (Web Browser). Affected by this vulnerability is an unknown function of the component WebKit. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability.

The weakness was released 09/16/2020 by Marcin Noga (Icewall) with Cisco Talos as HT211845 as confirmed advisory (Website). It is possible to read the advisory at support.apple.com. This vulnerability is known as CVE-2020-9951. The attack can be launched remotely. The exploitation doesn't need any form of authentication. 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 pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 07/08/2025). The advisory points out:

A use after free issue was addressed with improved memory management.

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 14.0 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (241427). Entries connected to this vulnerability are available at VDB-161370, VDB-161373 and VDB-161372. Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Web Browser

Vendor

• Apple

Name

• Safari

Version

• 13.1.0
• 13.1.1
• 13.1.2

License

• commercial

Website

• Vendor: https://www.apple.com/

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CPE 2.2info

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

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