A null pointer dereference was addressed with improved input validation. This issue is fixed in iOS 18.4 and iPadOS 18.4, macOS Sequoia 15.4, tvOS 18.4, visionOS 2.4. An attacker on the local network may be able to cause a denial-of-service.
https://support.apple.com/en-us/122378
https://support.apple.com/en-us/122377