Apple Safari/iOS/iPadOS/macOS up to 26.5.1 Website denial of service

Summaryinfo

A vulnerability identified as problematic has been detected in Apple Safari, iOS, iPadOS and macOS up to 26.5.1. This issue affects some unknown processing of the component Website Handler. This manipulation causes denial of service. The identification of this vulnerability is CVE-2026-43701. It is possible to initiate the attack remotely. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability has been found in Apple Safari, iOS, iPadOS and macOS up to 26.5.1 and classified as problematic. Affected by this vulnerability is some unknown functionality of the component Website Handler. The manipulation with an unknown input leads to a denial of service vulnerability. The CWE definition for the vulnerability is CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. As an impact it is known to affect availability. The summary by CVE is:

The issue was addressed with improved checks. This issue is fixed in Safari 26.5.2, iOS 26.5.2 and iPadOS 26.5.2, macOS Tahoe 26.5.2. A malicious website may be able to process restricted web content outside the sandbox.

It is possible to read the advisory at support.apple.com. This vulnerability is known as CVE-2026-43701 since 05/02/2026. The exploitation appears to be easy. 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 $5k-$25k at the moment (estimation calculated on 06/30/2026). The attack technique deployed by this issue is T1499 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 323673 (macOS 26.x < 26.5.2 Multiple Vulnerabilities (127595)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 26.5.2 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (323673). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

• Web Browser

Vendor

• Apple

Name

• iOS
• iPadOS
• macOS
• Safari

Version

• 26.5.0
• 26.5.1

License

• commercial

Website

• Vendor: https://www.apple.com/

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Be aware that VulDB is the high quality source for vulnerability data.

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