[tags:wwdc20-10095]

Hi, I’m implementing a macOS DNS Proxy as a system extension and running into a persistent activation error: OSSystemExtensionErrorDomain error 9 (validationFailed) with the message: extension category returned error This happens both on an MDM‑managed Mac and on a completely clean Mac (no MDM, fresh install). Setup macOS: 15.x (clean machine, no MDM) Xcode: 16.x Team ID: AAAAAAA111 (test) Host app bundle ID: com.example.agent.NetShieldProxy DNS Proxy system extension bundle ID: com.example.agent.NetShieldProxy.dnsProxy The DNS Proxy is implemented as a NetworkExtension system extension, not an app extension. Host app entitlements From codesign -d --entitlements :- /Applications/NetShieldProxy.app: xml com.apple.application-identifier AAAAAAA111.com.example.agent.NetShieldProxy com.apple.developer.system-extension.install com.apple.developer.team-identifier AAAAAAA111 com.apple.security.app-sandbox com.apple.security.application-groups group.com.example.NetShieldmac com.apple.security.files.user-selected.

We have an application which is written in Swift, which activates Transparent Proxy network extension. Our Transparent Proxy module is a system extension, which is exposing an app proxy provider interface (We are using NETransparentProxyProvider class and in extension’s Info.plist we use com.apple.networkextension.app-proxy key.) Sometimes we have observed that on starting the transparent proxy extension, the startProxy overridden delegate method(override func startProxy(options: [String : Any]?, completionHandler: @escaping (Error?) -> Void) {) in our AppProxyProvider class which is derived from NETransparentProxyProvider being called more than once for the same extension(pid). This leads to Over-resume of an object crash as we invoke setTunnelNetworkSettings inside the startProxy delegate. As this is controlled by the system, we are not sure why this delegate being called more than once sometimes even if we call the start TransparentProxy only once. Note that, this issue is seen only in Mac OS Tahoe. App

Hi everyone, Has anyone seen notarization behave like this? We have one specific app (let’s call it App A) with a Network Extension system extension. Whenever we submit App A for notarization: • Its submission stays “In Progress” indefinitely • The provisioning profile for its system extension becomes Invalid on its own • All our other apps suddenly fail notarization • And the whole team immediately gets: StatusCode 7000 – “Team is not yet configured for notarization.” Apple Support restored notarization once(Case 102738171569), and we confirmed other apps notarize fine — until we submit App A again, which instantly triggers the same team-wide block. This cycle has repeated twice. We verified: • Hardened runtime • Proper system extension signing • No private API usage • No get-task-allow • No ATS violations What’s confusing is that this doesn’t look like a normal notarization rejection. Normal failures don’t invalidate provisioning profiles or disable notarization for the entire team. It feels more like an au

Hi all, I have a working macOS (Intel) system extension app that currently uses only a Content Filter (NEFilterDataProvider). I need to capture/log HTTP and HTTPS traffic in plain text, and I understand NETransparentProxyProvider is the right extension type for that. For HTTPS I will need TLS inspection / a MITM proxy — I’m new to that and unsure how complex it will be. For DNS data (in plain text), can I use the same extension, or do I need a separate extension type such as NEPacketTunnelProvider, NEFilterPacketProvider, or NEDNSProxyProvider? Current architecture: Two Xcode targets: MainApp and a SystemExtension target. The SystemExtension target contains multiple network extension types. MainApp ↔ SystemExtension communicate via a bidirectional NSXPC connection. I can already enable two extensions (Content Filter and TransparentProxy). With the NETransparentProxy, I still need to implement HTTPS capture. Questions I’d appreciate help with: Can NETransparentProxy capture the DNS fields I need (dns_hostname,

Hi everyone, I’m developing an Electron application on macOS and I’m trying to register and activate a macOS System Extension, but I’m running into startup and entitlement issues. 🔧 What I’m trying to build • An Electron app packaged with electron-builder • Signed with Developer ID Application • Notarized using @electron/notarize • A macOS System Extension is already built and signed • The System Extension provides a virtual camera • I wrote a Swift helper that: • Registers / activates the virtual camera • Calls OSSystemExtensionManager • This Swift code is compiled into a .node native addon • The .node module is loaded and called from Electron (Node.js) to trigger system extension registration ❗ The problem When I add the following entitlement: com.apple.developer.system-extension.install the application fails to launch at all on macOS. Without this entitlement: • The app launches normally • But system extension activation fails with: Error Domain=OSSystemExtensionErrorDomain Code=2 Missing entitlement com.

This is just an FYI in case someone else runs into this problem. This afternoon (12 Dec 2025), I updated to macOS 26.2 and lost my network. The System Settings' Wi-Fi light was green and said it was connected, but traceroute showed No route to host. I turned Wi-Fi on & off. I rebooted the Mac. I rebooted the eero network. I switched to tethering to my iPhone. I switched to physical ethernet cable. Nothing worked. Then I remembered I had a beta of an app with a network system extension that was distributed through TestFlight. I deleted the app, and networking came right back. I had this same problem ~2 years ago. Same story: app with network system extension + TestFlight + macOS update = lost network. (My TestFlight build might have expired, but I'm not certain) I don't know if anyone else has had this problem, but I thought I'd share this in case it helps.

NEAppProxyUDPFlow contains below property: open var localEndpoint: NWEndpoint? { get } Why is localEndpoint not available for NEAppProxyTCPFlow? Is there a way to determine the source port of a flow of type NEAppProxyTCPFlow within the following method of NETransparentProxyProvider? override func handleNewFlow(_ flow: NEAppProxyFlow) -> Bool {

I'm currently observing a problem similar to this thread https://developer.apple.com/forums/thread/737334 The difference is that this is happening after updating a system extension. Basically same error, sysextd complains it can not check that the system extension is notarized: macOS Error 3 + Error code=-67050. I think macOS (Sequoia 15.3.2 or 15.7.2 if it matters) is wrong in this case for the following reasons: when using spctl assess -t install, the system extension is reported to be correctly notarized. when restarting the Mac, the updated system extension is correctly checked and staged. if I run spctl assess before sysextd tries to check the system extension, it works. I'm currently thinking of 2 reasons why the check does not work: sysextd is somehow trying to work with a cached assessment that has become invalid after the system extension was updated. macOS needs way more time between the update of the files and the request to update the staged extension. I tried adding a 5-second delay. This does no

Hi Team, I have a Network Extension application and UI frontend for it. The UI frontend talks to the Network Extension using XPC, as provided by NEMachServiceName. On M2 machine, The application and XPC connection works fine on clean installation. But, when the application is upgraded, the XPC connection keeps failing. Upgrade steps: PreInstall script kills the running processes, both UI and Network Extension Let installation continue PostInstall script to launch the application after installation complete. Following code is successful to the point of resume from UI application NSXPCInterface *exportedInterface = [NSXPCInterface interfaceWithProtocol:@protocol(IPCUIObject)]; newConnection.exportedInterface = exportedInterface; newConnection.exportedObject = delegate; NSXPCInterface *remoteObjectInterface = [NSXPCInterface interfaceWithProtocol:@protocol(IPCExtObject)]; newConnection.remoteObjectInterface = remoteObjectInterface; self.currentConnection = newConnection; [newConnection resume]; But it fails to g

I’m using an NETransparentProxyProvider where I add UDP-53 rules to intercept DNS queries from a private application. These queries are resolved locally on the endpoint by returning a custom DNS response. Example Rules look like this: NENetworkRule(destinationHost: NWHostEndpoint(hostname: mypaapp.com, port: 53),protocol:.UDP) This works as expected through browser and ping. handleNewUDPFlow/handleNewFlow with NEAppProxyUDPFlow gets called where custom dns response get written. Using nslookup mypaapp.com doesn't works. Why does this behaves differently for nslookup?

Description: We are investigating an issue where running a specific e-commerce iOS app inside the Xcode Simulator intermittently disrupts the Mac’s network connectivity. When the app is launched in the Simulator, our NETransparentProxyProvider and NEFilterDataProvider extensions occasionally stop receiving traffic correctly, and shortly afterward the entire macOS DNS resolution fails. Once this happens, all apps on the Mac lose internet access until mac is restarted. Disabling extensions also fixing the issue. This issue only appears when the app runs in the Xcode Simulator. I would like to confirm: Is it possible for traffic patterns or network behavior inside the Simulator to interfere with system-level Network Extension providers on macOS? Are there known limitations or conflicts between the Simulator’s virtual networking interfaces and Network Extensions? Any recommended debugging steps or best practices to isolate this behavior? Any guidance, known issues, or suggestions would be appreciated.

First time working with DEXT, so I'm trying to make Communicating between a DriverKit extension and a client app sample project to work and I'm having trouble. I'm following the steps for Automatically manage signing. It seems that the step “Sign to Run Locally” is wrong now, so I let it to Apple Developer. Now I have a Provisioning Profile error that says it doesn't include the com.apple.developer.driverkit.allow-any-userclient-access entitlement. If I go to Certificates, Identifiers and Profiles for this AppID and go to Capability Requests and select DriverKit Allow Any UserClient Access, this bring me to a page where I select DriverKit Entitlement but Any UserClient Access is not a choice. I tried asking for UserClient Access but the request has been denied saying that the engineering team does not think these entitlements are necessary for testing locally. So I removed com.apple.developer.driverkit.allow-any-userclient-access from NullDriver.entitlements. I can now install the DEXT but when I try Communic

We're distributing a virtual camera with our app that does not profit in the slightest from automatically applied system video effects both to the video going in (physical camera device) or out (virtual camera device). I'm aware of setting NSCameraReactionEffectGesturesEnabledDefault in Info.plist and determining active video effects via AVCaptureDevice API. Those are obviously crutches, because having to tell users to go look for and click around in menu bar apps is the opposite of a great UX. To make our product's video output more deterministic, I'm looking for a way to tell the CMIO subsystem that our virtual camera does not support any of the system video effects. I'm seeing properties like AVCaptureDevice.Format.isPortraitEffectSupported and AVCaptureDevice.Format.isStudioLightSupported whose documentation refers to the format's ability to support these effects. Since we're setting a CMFormatDescription via CMIOExtensionStreamSource.formats I was hoping to find something in the extensions, but wasn't su

We have a content filter system extension as part of our macOS app. The filter normally works correctly, activation and deactivation works as expected but occasionally we see an issue when the content filter is activated. When this issues occurs, the filter activation appears to behave correctly, no errors are reported. Using systemextensionsctl list we see the filter is labelled as [activated enabled]. However, the installed content filter executable does not run. We have seen this issue on macOS 15.3 and later and on the beta macOS 26.1 RC. It happens only occasionally but when it does there is no indication as to why the executable is not running. There are no crash logs or errors in launchd logs. Both rebooting and deactivating/activating the filter do not resolve the issue. The only fix appears to be completely uninstalling the app (including content filter) and reinstalling. I have raised a FB ticket, FB20866080. Does anyone have any idea what could cause this?

Hi, when I perform an overlay installation via a PKG on macOS for an application containing the NEFilterDataProvider functionality, there is a chance that the entire system network becomes unreachable. Disabling the corresponding Content Filter in System Settings > Network > Filters immediately restores network connectivity. This issue does not occur every time, with a frequency of approximately 1 in 20 installation attempts.  The following details may help identify the problem: The Filter.app containing the NEFilterDataProvider resides within the main app's Resources directory, e.g., /Applications/Main.app/Contents/Resources/Filter.app Main.app is installed via a PKG; the issue typically occurs during an overlay installation of Main.app. The NEFilterDataProvider operates as a System Extension. The func handleNewFlow(_ flow: NEFilterFlow) -> NEFilterNewFlowVerdict {} returns .allow. Wireshark packet captures show TCP packets but no UDP packets; TCP handshakes cannot complete. Disabling the correspon