An out-of-bounds write issue was addressed with improved input validation. This issue is fixed in iOS 18.4 and iPadOS 18.4, macOS Sequoia 15.4, visionOS 2.4, watchOS 11.4. An app may be able to cause unexpected system termination or write kernel memory.
https://support.apple.com/en-us/122378
https://support.apple.com/en-us/122376
https://support.apple.com/en-us/122373
https://support.apple.com/en-us/122371
http://seclists.org/fulldisclosure/2025/Apr/8
http://seclists.org/fulldisclosure/2025/Apr/4