Summary: EASession initialization consistently returns nil on iOS 27 when connecting to a MFi-certified USB accessory. The same code and accessory work correctly on iOS 26. Apple's official EADemo sample code also fails on iOS 27. Steps to Reproduce: Connect MFi-certified USB accessory to iOS 27 device via Lightning/USB-C Observe that EAAccessory is detected: connected=YES, connectionID=34951162 Confirm protocol string is in accessory.protocolStrings Call [[EASession alloc] initWithAccessory:accessory forProtocol:@"*******"] EASession returns nil Expected Results: EASession should be created successfully, allowing input/output stream configuration. This works correctly on iOS 26 with identical code and accessory. Actual Results: EASession returns nil. System log shows: "[#ExternalAccessory] ERROR - .../EASession.m:-[EASession dealloc] - 212 unable to close session for _accessory=0x1513d3bb0 and sessionID=65536" Note: sessionID=65536 indicates EASession was partially created but immediately deallocated. Configuration: Device: 所有机型 iOS Version: 27.0 beta Xcode Version: 26.3 (17C529) Build SDK: iOS 26 SDK Accessory PPID: cfc Accessory Firmware: L.B.1 Accessory Hardware: 1.0.1 App: Both our production app and Apple's official EADemo sample code Info.plist Configuration: UISupportedExternalAccessoryProtocols includes "*****" UIBackgroundModes includes "external-accessory" Device Settings: Settings > Privacy & Security > Security > Wired Accessories: "Automatically Allow When Unlocked" Additional Notes: EAAccessory object is properly created and accessible Accessory protocol string matches exactly All MFi certificates present (certSerial: 16 bytes, certData: 608 bytes) Issue reproduced with Apple's official EADemo sample code, confirming this is not an application-level bug Issue does NOT occur on iOS 26 with same device and accessory Regression: iOS 26: Works correctly iOS 27: Fails consistently

There is a problem with the Apple local network setting api, iOS18 system, you turn off the local network permissions of the APP, uninstall the APP, and then re-install, the local network permissions even if opened, there is no effect, only restart the phone is useful