CVE-2023-40441 is a denial-of-service vulnerability affecting Apple iOS and iPadOS devices, caused by a resource exhaustion issue during the processing of web content. The root cause is insufficient input validation, which allows specially crafted web content to consume excessive system resources, leading to a DoS condition that can disrupt normal device operation. This vulnerability impacts Apple mobile operating systems prior to iOS 17 and iPadOS 17, as well as macOS Sonoma 14, where the issue has been fixed. The vulnerability does not require authentication or user interaction beyond processing the malicious web content, which could be delivered via web browsing or embedded content in apps. Although no exploits have been reported in the wild, the potential for denial-of-service attacks exists, especially in environments where devices frequently access untrusted web content. The lack of a CVSS score necessitates an assessment based on impact and exploitability factors. The vulnerability primarily threatens availability by causing device unresponsiveness or crashes, with no direct impact on confidentiality or integrity. The ease of exploitation is moderate since it requires delivering crafted web content, but no user interaction beyond content processing is needed. The scope is limited to Apple mobile devices running vulnerable OS versions. This vulnerability highlights the importance of robust input validation in web content processing components of mobile operating systems.

For European organizations, this vulnerability poses a risk of denial-of-service on Apple iOS and iPadOS devices, potentially disrupting business operations reliant on mobile devices. Critical sectors such as finance, healthcare, and government, which often use Apple devices for secure communications and mobile workflows, could experience interruptions. The DoS condition could lead to temporary loss of device availability, impacting productivity and possibly delaying critical communications. While the vulnerability does not expose sensitive data or allow unauthorized access, the operational impact of device unavailability can be significant, especially in environments with high dependency on mobile platforms. Organizations with Bring Your Own Device (BYOD) policies may face additional challenges in ensuring all devices are updated promptly. The absence of known exploits reduces immediate risk but does not eliminate the threat, as attackers could develop exploits targeting unpatched devices. European organizations should consider the risk in their mobile device management and incident response planning.

To mitigate CVE-2023-40441, European organizations should prioritize updating all Apple iOS and iPadOS devices to iOS 17, iPadOS 17, or later versions where the vulnerability is fixed. Mobile device management (MDM) solutions should be leveraged to enforce timely patch deployment and compliance monitoring. Network-level protections can include filtering or blocking access to suspicious or untrusted web content sources to reduce exposure to crafted content that could trigger the DoS. Educating users about the risks of accessing unknown or untrusted websites and encouraging cautious browsing behavior can further reduce risk. Organizations should also monitor device performance and logs for signs of resource exhaustion or abnormal crashes that may indicate exploitation attempts. Implementing web content filtering and sandboxing technologies on mobile devices can help isolate potentially malicious content. Finally, incident response plans should include procedures for handling mobile device outages caused by this vulnerability.