General: Forums topic: Privacy & Security Privacy Resources Security Resources Share and Enjoy — Quinn “The Eskimo!” @ Developer Technical Support @ Apple let myEmail = "eskimo" + "1" + "@" + "apple.com"

This is a recap of the Q&A from the Meet with Apple activity Fortify your app: Essential strategies to strengthen security. If you attended the event and asked questions, thank you for coming and participating! If you weren’t able to join us live we hope this recap is useful. Memory Integrity Enforcement (MTE) What is Memory Integrity Enforcement and which devices support it? Memory Integrity Enforcement is supported on A19, A19 Pro, M5, M5 Pro, and M5 Max chips, which power iPhone 17e, the new MacBook Air (M5), and the new MacBook Pro (M5 Pro or M5 Max). Starting in the 26.4 OS versions, applications that enable MTE (checked-allocations) as part of Enhanced Security will also run with MTE enabled in the simulator when running on macOS hardware that supports MTE. How can I use Memory Integrity Enforcement with third-party SDKs? Third-party SDKs linked into your app will generally use the system allocator automatically and benefit from Memory Integrity Enforcement automatically. If there are memory corruption bugs in those SDKs that Memory Integrity Enforcement features like MTE detect and turn into crashes, you'll want to work with the developers of those SDKs to have them fix the underlying bugs. You could use MTE soft mode to avoid having those memory corruptions crash your app while you wait for fixes from the developers, at the cost of the relative reduction in security that entails. Why does my app crash on launch with MTE enabled, with tags showing as 0? Tag-check violations where the ltag (logical tag) is 0 and the atag (actual tag) is non-zero can be caused by code patterns that strip the high bits that the ltag is stored in and fail to restore them before use. Additionally, arm64 binaries produced by older versions of clang may have issues where the tag is incorrectly stripped from the pointer. Recompiling the binary with a recent compiler should remediate the issue. Can I use Memory Integrity Enforcement with older Swift versions? Yes, Memory Integrity Enforcement can be used with any Swift version. Pointer Authentication (PAC) How does Pointer Authentication work and why is it opt-in? PAC is an opt-in feature because although adopting PAC is frequently as easy as turning on the compiler flag, some software is not trivially compatible. For example, while it mostly works in arm64 to memcpy a C++ object, this is invalid and generates fatal exceptions in arm64e. Additionally, PAC is a compile time change as it requires different instructions throughout the program. Pointer authentication makes it more difficult to create a pointer (from an integer) or to modify an existing pointer. This complements technologies such as MTE (which can catch many bound and lifetime errors) and typed allocation (which mitigates the effects of memory re-use). Where are the cryptographic keys for Pointer Authentication stored? The keys used for generating PAC signatures are stored in the CPU itself as specified by the ARM architecture. These keys are ephemeral and can change across process launches and boots, depending on which PAC key is used. The signatures are, however, stored in the upper bits of the pointer itself. How does Pointer Authentication work with Objective-C method swizzling? When you use the functions provided by the ObjC runtime, they ensure that any necessary pointer signing is correctly handled. What deployment targets and OS versions support Pointer Authentication? PAC is tied to the arm64e architecture. arm64e is first supported in iOS 17.4, and generally supported starting with iOS 26 and macOS 26. Universal binaries can be built for arm64e + arm64, and arm64 will be used when arm64e isn't supported. When building the universal binary, both architectures can be compiled for an older deployment target, but keep in mind that arm64e will only be used on newer iOS. How do I enable Pointer Authentication in modular apps? arm64e is indeed required, and every target that contributes binary code that's linked or dynamically loaded into an app does need to have arm64e added as an architecture. When enabling the Enhanced Security capability, Xcode adds the ENABLE_POINTER_AUTHENTICATION build setting (that adds arm64e) as needed, but you may need to add that separately as well. Bounds Safety and Annotations How do bounds safety checks work in Clang? With -fbounds-safety enabled Clang will emit bounds checks wherever pointers are dereferenced or reassigned (exception: assigning to __bidi_indexable does not trigger a bounds check, since __bidi_indexable can track the fact that the pointer is out of bounds and defer the bounds check). If the bounds check fails the program will jump to an instruction that traps the process. Clang uses a combination of static analysis and runtime checks to enforce that pointer bounds are respected. How can I work with libraries that don't have bounds annotations? Forging safe pointers at the boundary (using __unsafe_forge_single etc.) is the recommended approach when interoperating with libraries that do not have bounds annotations, when you want to be explicit about the fact that you're interacting with unsafe code. This makes it easy to grep for "unsafe" in your code base when doing a security audit. If you are confident that the API adheres to a bounds safe interface but simply lacks the annotations, you can redeclare the signature in your local header with added bounds annotations, like this: //--- system_header.h bar_t * /* implicitly __unsafe_indexable */ foo(); //--- project_header.h #include <ptrcheck.h> #include <system_header.h> bar_t * __single foo(); How can I safely pass Swift data to C/C++ functions? This is a great question! Automatically generated wrapper functions that safely unwrap Span types and pass along the pointer to C/C++ is a feature available since Xcode 26 when the experimental feature SafeInteropWrappers is enabled. This requires annotating std::span<T> parameters with __noescape, or pointer parameters with both __noescape and __counted_by/__sized_by, directly in the header or using API notes. Note that this is only safe if Swift can accurately track the lifetime of the unwrapped pointer, which is why the Span wrapper is not generated without the __noescape annotation. Since this is an experimental feature with ongoing development, questions and feedback on the Swift forums are extra welcome to help us shape and stabilize this feature! Continued in next post...

I have two applications, and I recently decided to add the Apple Sign In feature. Initially, I configured it for one of the apps as the Primary ID for this feature. Everything worked well, and I decided to add it to the second app. I made a mistake and used the First app as Primary ID using the "Group with an existing primary App ID" flag. Now, when I sign in using the second app, I don't see it in the list of apps in iPhone Settings for Apple Sign In; I only see the primary app. And with that, I no longer see a prompt for sharing/hiding email, and I am unable to revoke credentials correctly. I decided to change the Second app's Sign-in config and set it as the Primary ID for the feature. I was hoping to get two apps independent for the SignIn. However, it doesn't seem to make a difference. The second app behaves the same way, as long as the first app used SignIn, the second one always thinks that the user has already used that feature and never shows the correct prompt. Is there something I missed after changing the Configuration?

I was experiencing a weird sign in error when using apple sign in with my app and wanted to put it here for anyone else who might experience it in the future, and so apple can make this requirement more clear. I was using CloudKit and apple sign in. If you are not using both this probably does not apply to you. Every time I would go to sign in in the iOS simulator I would enter my password, hit "sign in", and everything just froze. The very odd reason for this is if you are using iCloudKit and apple sign in you need to go to specifically the "identifiers" in the "Certificates, Identifiers & Profiles" menu (https://developer.apple.com/account/resources/identifiers/list). And from there you specifically need an App ID Configuration with apple sign in enabled. From there you have to have the same exact bundle identifier in Xcode under project settings(not an upper tab just click your project in the left panel). And that should allow you to both pass validation and have your sign in work. Hope this helps!

I’ve been running into an issue for over a day when trying to create a Sign in with Apple key. Each time I attempt to download it, I’m redirected to a page that displays an error and provides no further guidance. I’ve contacted Support and haven’t yet received a reply. I’ve also tried across multiple browsers (Chrome, Safari, Firefox), including incognito modes. Any ideas on how to resolve this? We’re currently stuck and would appreciate guidance.

When implementing Sign In with Apple I created an App ID and a Service ID for my app. I didn't configure the Server-to-Server Notification URL properly there and token revocation didn't work. Later on I updated the url config and the name of the identifiers. However, when I Sign in with Apple in my app I still see the old identifier name in my iPhone Settings->Apple Account->Sign in with Apple. I would assume that if the name doesn't update, the configuration doesn't update either. I'm using automatic Xcode signing, I have deleted all the profiles locally, cleaned project, bumped versions, waited for a week, nothing worked. Token revocation for account deletion doesn't work properly I would assume because of the initial misconfiguration. I want to mention that this is working fine for my development build (another bundleID, AppID, ServiceID) What am I missing here?

I'm developing an iOS app that utilizes Universal Links and ASWebAuthenticationSession to deep-link from a website to the app itself. This implementation adheres to the recommendations outlined in RFC 8252, ensuring that the app opening the ASWebAuthenticationSession is the same app that is launched via the Universal Link. Problem: 　While most users can successfully launch the app via Universal Links,a few percent of users experience instances where the app fails to launch, and the user is redirected to the browser. What I've Tried: 　ASWebAuthenticationSession Configuration: I've double-checked the configuration of callbackURLScheme and presentationContextProvider. 　Universal Links: Verified the apple-app-site-association file and associated domains entitlement. 　Network Conditions: Tested on various network environments (Wi-Fi, cellular) and devices. Questions: 　What are the potential causes for this behavior? 　Has anyone else encountered a similar issue and found a solution? 　Are there any debugging techniques or ways to generate more detailed logs? I haven't been able to determine which device or OS version is causing this problem. Thank you.

There is a sudden surge of users in our apps with invalidated biometrics. Even though the issue is being handled correctly and the user has another way to login, some of the users forgot their passwords and they can not login. Is there any known issue with Biometrics in iOS 18.3.2 or later? There is a (possible) related discussion here: https://discussions.apple.com/thread/256011565

I keep getting the following error when trying to run Passkey sign in on macOS. Told not to present authorization sheet: Error Domain=com.apple.AuthenticationServicesCore.AuthorizationError Code=1 "(null)" ASAuthorizationController credential request failed with error: Error Domain=com.apple.AuthenticationServices.AuthorizationError Code=1004 "(null)" This is the specific error. Application with identifier a is not associated with domain b I have config the apple-app-site-association link and use ?mode=developer Could there be any reason for this?

Hi team, We are experiencing an issue where some users in China are unable to create passkeys due to authentication errors. This is the UI flows The method we use to prompt users is passkey creation. Technically, this is implemented using Apple’s AuthenticationServices framework. We create an instance of ASAuthorizationController and conform to ASAuthorizationControllerDelegate to handle the results of the authentication attempt. In failure cases, we receive ASAuthorizationError.failed (code 1004), along with some additional details describing the nature of the failure. However, we are currently unable to determine the exact root cause of this issue or how to resolve it. At this point, we can only make assumptions based on the limited error information provided. Our current hypothesis is that due to network restrictions, Apple may be unable to reach the .well-known endpoint where we host the associated domain file. Alternatively, even if the file is successfully loaded and cached to Apple’s CDN, the system in China may not be able to reach the CDN itself. We would greatly appreciate it if you could help us understand what might be causing this problem and guide us on how we can resolve it effectively. Thanks, Hung

I modified the system.login.screensaver rule in the authorization database to use "authenticate" instead of "use-login-window-ui" to display a custom authentication plugin view when the screensaver starts or the screen locks. However, I noticed an issue when the "Require Password after Display is Turned Off" setting is set to 5 minutes in lock screen settings: If I close my Mac’s lid and reopen it within 5 minutes, my authentication plugin view is displayed as expected. However, the screen is not in a locked state—the desktop remains accessible, and the black background that typically appears behind the lock screen is missing. This behavior differs from the default lock screen behavior, where the screen remains fully locked, and the desktop is hidden. Has anyone encountered this issue before? Is there a way to ensure the screen properly locks when using authenticate in the screensaver rule?

I've been fighting this issue for 3 days now. After several failures, I created a new app id and service id yesterday. I checked and entered domain, callback, and login usage clearly, but it keeps returning an error. Can you help me figure out what's wrong? https://appleid.apple.com/auth/authorize?response_type=code&client_id=com.smoothmail.signin&redirect_uri=https%3A%2F%2Fsmoothmail.store%2Fapple-auth&state=4157daa763&scope=name+email&response_mode=form_post

I set up "Sign in with Apple" via REST API according to the documentation. I can log in on my website and everything looks fine for the user. But I receive an email, that my "Sign in with Apple" account has been rejected by my own website. It states, I will have to re-submit my name and email address the next time I log in to this website. I don't see any error messages, no log entries, no HTTP errors anywhere. I also can't find anything in the docs, the emails seem to not be mentioned there, searching for anything with "rejected" in the forum did not yield any helpful result, because they are always about App entries being rejected etc. Did someone experience something similar yet? What's the reason, I'm getting these emails? I get them every time I go through the "Sign in with Apple" flow on my website again.

I've just implemented Sign-In-With-Apple and everything is working perfectly, but my app seems to be in some strange state where users are unable to remove it from the Sign-In-With-Apple section of their settings. Things I've tried: -- Deleting from Mac. (It just stays in the list) -- Deleting from the iPhone (It stays in the list) -- Deleting from account.apple.com (same issue) -- I've noticed in the browser inspector tools I receive a 200 on the DELETE request, but the app remains. -- Multiple users Also have tried: -- Revoking the token through the REST API -- I get an email saying the token has been revoked, but it's still working -- Same code, different app id (works fine!) It seems like maybe my app is in some sort of weird state? Has anyone come across this before?

Hi Community, We've implemented Sign In with Apple in our application. Our domains are properly registered in the developer console, but we're experiencing inconsistent email functionality with Apple's privacy email service. Some domains work correctly while others show delivery problems, even though all domains have identical configurations. Apple's console displays green verification status for all domains, yet testing reveals that emails to privacy-protected accounts don't arrive as expected. We're using SendGrid as our email service provider, and all domains have valid authentication records (SPF, DKIM, DMARC) in place. Has anyone encountered similar inconsistencies with Apple's privacy email service? Would appreciate any configuration tips or troubleshooting guidance. Thanks.

Hello Apple Developer Community, We have been experiencing a persistent notification issue in our application, Flowace, after updating to macOS 15 and above. The issue is affecting our customers but does not occur on our internal test machines. Issue Description When users share their screen using Flowace, they receive a repetitive system notification stating: "Flowace has accessed your screen and system audio XX times in the past 30 days. You can manage this in settings." This pop-up appears approximately every minute, even though screen sharing and audio access work correctly. This behavior was not present in macOS 15.1.1 or earlier versions and appears to be related to recent privacy enhancements in macOS. Impact on Users The frequent pop-ups disrupt workflows, making it difficult for users to focus while using screen-sharing features. No issues are detected in Privacy & Security Settings, where Flowace has the necessary permissions. The issue is not reproducible on our internal test machines, making troubleshooting difficult. Our application is enterprise level and works all the time, so technically this pop only comes after a period of not using the app. Request for Assistance We would like to understand: Has anyone else encountered a similar issue in macOS 15+? Is there official Apple documentation explaining this new privacy behavior? Are there any interim fixes to suppress or manage these notifications? What are Apple's prospects regarding this feature in upcoming macOS updates? A demonstration of the issue can be seen in the following video: https://youtu.be/njA6mam_Bgw Any insights, workarounds, or recommendations would be highly appreciated! Thank you in advance for your help. Best, Anuj Patil Flowace Team

WebAuthn Level 3 § 6.3.2 Step 2 states the authenticator must : Check if at least one of the specified combinations of PublicKeyCredentialType and cryptographic parameters in credTypesAndPubKeyAlgs is supported. If not, return an error code equivalent to "NotSupportedError" and terminate the operation. On my iPhone 15 Pro Max running iOS 18.5, Safari + Passwords does not exhibit this behavior; instead an error is not reported and an ES256 credential is created when an RP passes a non-empty sequence that does not contain {"type":"public-key","alg":-7} (e.g., [{"type":"public-key","alg":-8}]). When I use Chromium 138.0.7204.92 on my laptop running Arch Linux in conjunction with the Passwords app (connected via the "hybrid" protocol), a credential is not created and instead an error is reported per the spec.

Hi , I have a requirement like, Develop an app for iPad and app uses .net core apis. App will be in kiosk mode, and app doesn't have any type of authentication even OTP also. As the apis will be publishing to all over internet, how can we achieve security to apis? Kindly provide suggestions for this implementation

Hi everyone, I’m developing a multiplayer iOS game that uses Multipeer Connectivity for local peer-to-peer networking. I’d like to display user-assigned device names in the UI to help players identify each other during the connection process. In iOS 16 and later, accessing UIDevice.current.name requires the User-Assigned Device Name Entitlement. The documentation states that the entitlement is granted for functionality involving “interaction between multiple devices that the same user operates”. My game is strictly multiplayer, with devices owned by different users, not a single user managing multiple devices. I have a few questions regarding this: Does the requirement for “devices operated by the same user” definitively exclude multiplayer scenarios where devices belong to different players? Can a Multipeer Connectivity-based game qualify for the entitlement in this case? If the entitlement is not applicable, is prompting users to enter custom names the recommended approach for identifying devices in a multiplayer UI? Has anyone successfully obtained this entitlement for a similar multiplayer use case with Multipeer Connectivity? Thanks in advance.

I'm testing app transferring, before, I have migrate user from teamA to teamB, including subA->transferSub->subB process, now I'm transfer the app from teamB to teamC, after the transfer requested, I can't get transfer_id by /usermigrationinfo api, which response 400 invalid request. the question is I can still get transfer sub by the auth/token api(grant_type: authorization_code) with teamB parameters(teamIdB/clientIdB/appSecretB/redirectUrlB/subB)，but the value is same as first time transfer_id which get during teamA to teamB. when use parameters above with target(teamIdC) to request /usermigrationinfo, invalid request was responsed. im sure that all parameters is correct, dose it cause by teamB still in 60-days first transferring(sure already accepted)?

I regularly see folks confused by the difference in behaviour of app groups between macOS and iOS. There have been substantial changes in this space recently. While much of this is now covered in the official docs (r. 92322409), I’ve updated this post to go into all the gory details. If you have questions or comments, start a new thread with the details. Put it in the App & System Services > Core OS topic area and tag it with Code Signing and Entitlements. Oh, and if your question is about app group containers, also include Files and Storage. Share and Enjoy — Quinn “The Eskimo!” @ Developer Technical Support @ Apple let myEmail = "eskimo" + "1" + "@" + "apple.com" App Groups: macOS vs iOS: Working Towards Harmony There are two styles of app group ID: iOS-style app group IDs start with group., for example, group.eskimo1.test. macOS-style app group IDs start with your Team ID, for example, SKMME9E2Y8.eskimo1.test. This difference has been the source of numerous weird problems over the years. Starting in Feb 2025, iOS-style app group IDs are fully supported on macOS for all product types [1]. If you’re writing new code that uses app groups, use an iOS-style app group ID. If you have existing code that uses a macOS-style app group ID, consider how you might transition to the iOS style. IMPORTANT The Feb 2025 changes aren’t tied to an OS release but rather to a Developer website update. For more on this, see Feb 2025 Changes, below. [1] If your product is a standalone executable, like a daemon or agent, wrap it in an app-like structure, as explained in Signing a daemon with a restricted entitlement. iOS-Style App Group IDs An iOS-style app group ID has the following features: It starts with the group. prefix, for example, group.eskimo1.test. You allocate it on the Developer website. This assigns the app group ID to your team. You then claim access to it by listing it in the App Groups entitlement (com.apple.security.application-groups) entitlement. That claim must be authorised by a provisioning profile [1]. The Developer website will only let you include your team’s app group IDs in your profile. For more background on provisioning profiles, see TN3125 Inside Code Signing: Provisioning Profiles. iOS-style app group IDs originated on iOS with iOS 3.0. They’ve always been supported on iOS’s child platforms (iPadOS, tvOS, visionOS, and watchOS). On the Mac: They’ve been supported by Mac Catalyst since that technology was introduced. Likewise for iOS Apps on Mac. Starting in Feb 2025, they’re supported for other Mac products. [1] Strictly speaking macOS does not require that, but if your claim is not authorised by a profile then you might run into other problems. See Entitlements-Validated Flag, below. macOS-Style App Group IDs A macOS-style app group ID has the following features: It should start with your Team ID [1], for example, SKMME9E2Y8.eskimo1.test. It can’t be explicitly allocated on the Developer website. Code that isn’t sandboxed doesn’t need to claim the app group ID in the App Groups entitlement. [2] To use an app group, claim the app group ID in the App Groups entitlement. The App Groups entitlement is not restricted on macOS, meaning that this claim doesn’t need to be authorised by a provisioning profile [3]. However, if you claim an app group ID that’s not authorised in some way, you might run into problems. More on that later in this post. If you submit an app to the Mac App Store, the submission process checks that your app group IDs make sense, that is, they either start with your Team ID (macOS style) or are assigned to your team (iOS style). [1] This is “should” because, historically, macOS has not actually required it. However, that’s now changing, with things like app group container protection. [2] This was true prior to macOS 15. It may still technically be true in macOS 15 and later, but the most important thing, access to the app group container, requires the entitlement because of app group container protection. [3] Technically it’s a validation-required entitlement, something that we’ll come back to in the Entitlements-Validated Flag section. Feb 2025 Changes On 21 Feb 2025 we rolled out a change to the Developer website that completes the support for iOS-style app group IDs on the Mac. Specifically, it’s now possible to create a Mac provisioning profile that authorises the use of an iOS-style app group ID. Note This change doesn’t affect Mac Catalyst or iOS Apps on Mac, which have always been able to use iOS-style app group IDs on the Mac. Prior to this change it was possible to use an iOS-style app group ID on the Mac but that might result in some weird behaviour. Later sections of this post describe some of those problems. Of course, that information is now only of historical interest because, if you’re using an iOS-style app group, you can and should authorise that use with a provisioning profile. We also started seeding Xcode 16.3, which has since been release. This is aware of the Developer website change, and its Signing & Capabilities editor actively encourages you to use iOS-style app groups IDs in all products. Note This Xcode behaviour is the only option for iOS and its child platforms. With Xcode 16.3, it’s now the default for macOS as well. If you have existing project, enable this behaviour using the Register App Groups build setting. Finally, we updated a number of app group documentation pages, including App Groups entitlement and Configuring app groups. Crossing the Streams In some circumstances you might need to have a single app that accesses both an iOS- and a macOS-style app group. For example: You have a macOS app. You want to migrate to an iOS-style app group ID, perhaps because you want to share an app group container with a Mac Catalyst app. But you also need to access existing content in a container identified by a macOS-style app group ID. Historically this caused problems (FB16664827) but, as of Jun 2025, this is fully supported (r. 148552377). When the Developer website generates a Mac provisioning profile for an App ID with the App Groups capability, it automatically adds TEAM_ID.* to the list of app group IDs authorised by that profile (where TEAM_ID is your Team ID). This allows the app to claim access to every iOS-style app group ID associated with the App ID and any macOS-style app group IDs for that team. This helps in two circumstances: It avoids any Mac App Store Connect submission problems, because App Store Connect can see that the app’s profile authorises its use of all the it app group IDs it claims access to. Outside of App Store — for example, when you directly distribute an app using Developer ID signing — you no longer have to rely on macOS granting implicit access to macOS-style app group IDs. Rather, such access is explicitly authorised by your profile. That ensures that your entitlements remain validated, as discussed in the Entitlements-Validated Flag, below. A Historical Interlude These different styles of app group IDs have historical roots: On iOS, third-party apps have always used provisioning profiles, and thus the App Groups entitlement is restricted just like any other entitlement. On macOS, support for app groups was introduced before macOS had general support for provisioning profiles [1], and thus the App Groups entitlement is unrestricted. The unrestricted nature of this entitlement poses two problems. The first is accidental collisions. How do you prevent folks from accidentally using an app group ID that’s in use by some other developer? On iOS this is easy: The Developer website assigns each app group ID to a specific team, which guarantees uniqueness. macOS achieved a similar result by using the Team ID as a prefix. The second problem is malicious reuse. How do you prevent a Mac app from accessing the app group containers of some other team? Again, this isn’t an issue on iOS because the App Groups entitlement is restricted. On macOS the solution was for the Mac App Store to prevent you from publishing an app that used an app group ID that’s used by another team. However, this only works for Mac App Store apps. Directly distributed apps were free to access app group containers of any other app. That was considered acceptable back when the Mac App Store was first introduced. That’s no longer the case, which is why macOS 15 introduced app group container protection. See App Group Container Protection, below. [1] I’m specifically talking about provisioning profiles for directly distributed apps, that is, apps using Developer ID signing. Entitlements-Validated Flag The fact that the App Groups entitlement is unrestricted on macOS is, when you think about it, a little odd. The purpose of entitlements is to gate access to functionality. If an entitlement isn’t restricted, it’s not much of a gate! For most unrestricted entitlements that’s not a problem. Specifically, for both the App Sandbox and Hardened Runtime entitlements, those are things you opt in to, so macOS is happy to accept the entitlement at face value. After all, if you want to cheat you can just not opt in [1]. However, this isn’t the case for the App Groups entitlement, which actually gates access to functionality. Dealing with this requires macOS to walk a fine line between security and compatibility. Part of that solution is the entitlements-validated flag. When a process runs an executable, macOS checks its entitlements. There are two categories: Restricted entitlements must be authorised by a provisioning profile. If your process runs an executable that claims a restricted entitlement that’s not authorised by a profile, the system traps. Unrestricted entitlements don’t have to be authorised by a provisioning profile; they can be used by any code at any time. However, the App Groups entitlement is a special type of unrestricted entitlement called a validation-required entitlement. If a process runs an executable that claims a validation-required entitlement and that claim is not authorised by a profile, the system allows the process to continue running but clears its entitlements-validated flag. Some subsystems gate functionality on the entitlements-validated flag. For example, the data protection keychain uses entitlements as part of its access control model, but refuses to honour those entitlements if the entitlement-validated flag has been cleared. Note If you’re curious about this flag, use the procinfo subcommand of launchctl to view it. For example: % sudo launchctl procinfo `pgrep Test20230126` … code signing info = valid … entitlements validated … If the flag has been cleared, this line will be missing from the code signing info section. Historically this was a serious problem because it prevented you from creating an app that uses both app groups and the data protection keychain [2] (r. 104859788). Fortunately that’s no longer an issue because the Developer website now lets you include the App Groups entitlement in macOS provisioning profiles. [1] From the perspective of macOS checking entitlements at runtime. There are other checks: The App Sandbox is mandatory for Mac App Store apps, but that’s checked when you upload the app to App Store Connect. Directly distributed apps must be notarised to pass Gatekeeper, and the notary service requires that all executables enable the hardened runtime. [2] See TN3137 On Mac keychain APIs and implementations for more about the data protection keychain. App Groups and the Keychain The differences described above explain a historical oddity associated with keychain access. The Sharing access to keychain items among a collection of apps article says: Application groups When you collect related apps into an application group using the App Groups entitlement, they share access to a group container, and gain the ability to message each other in certain ways. You can use app group names as keychain access group names, without adding them to the Keychain Access Groups entitlement. On iOS this makes a lot of sense: The App Groups entitlement is a restricted entitlement on iOS. The Developer website assigns each iOS-style app group ID to a specific team, which guarantees uniqueness. The required group. prefix means that these keychain access groups can’t collide with other keychain access groups, which all start with an App ID prefix (there’s also Apple-only keychain access groups that start with other prefixes, like apple). However, this didn’t work on macOS [1] because the App Groups entitlement is unrestricted there. However, with the Feb 2025 changes it should now be possible to use an iOS-style app group ID as a keychain access group on macOS. Note I say “should” because I’ve not actually tried it (-: Keep in mind that standard keychain access groups are protected the same way on all platforms, using the restricted Keychain Access Groups entitlement (keychain-access-groups). [1] Except for Mac Catalyst apps and iOS Apps on Mac. Not Entirely Unsatisfied When you launch a Mac app that uses app groups you might see this log entry: type: error time: 10:41:35.858009+0000 process: taskgated-helper subsystem: com.apple.ManagedClient category: ProvisioningProfiles message: com.example.apple-samplecode.Test92322409: Unsatisfied entitlements: com.apple.security.application-groups Note The exact format of that log entry, and the circumstances under which it’s generated, varies by platform. On macOS 13.0.1 I was able to generate it by running a sandboxed app that claims a macOS-style app group ID in the App Groups entitlement and also claims some other restricted entitlement. This looks kinda worrying and can be the source of problems. It means that the App Groups entitlement claims an entitlement that’s not authorised by a provisioning profile. On iOS this would trap, but on macOS the system allows the process to continue running. It does, however, clear the entitlements-validate flag. See Entitlements-Validated Flag for an in-depth discussion of this. The easiest way to avoid this problem is to authorise your app group ID claims with a provisioning profile. If there’s some reason you can’t do that, watch out for potential problems with: The data protection keychain — See the discussion of that in the Entitlements-Validated Flag and App Groups and the Keychain sections, both above. App group container protection — See App Group Container Protection, below. App Group Container Protection macOS 15 introduced app group container protection. To access an app group container without user intervention: Claim access to the app group by listing its ID in the App Groups entitlement. Locate the container by calling the containerURL(forSecurityApplicationGroupIdentifier:) method. Ensure that at least one of the following criteria are met: Your app is deployed via the Mac App Store (A). Or via TestFlight when running on macOS 15.1 or later (B). Or the app group ID starts with your app’s Team ID (C). Or your app’s claim to the app group is authorised by a provisioning profile embedded in the app (D) [1]. If your app doesn’t follow these rules, the system prompts the user to approve its access to the container. If granted, that consent applies only for the duration of that app instance. For more on this, see: The System Integrity Protection section of the macOS Sequoia 15 Release Notes The System Integrity Protection section of the macOS Sequoia 15.1 Release Notes WWDC 2024 Session 10123 What’s new in privacy, starting at 12:23 The above criteria mean that you rarely run into the app group authorisation prompt. If you encounter a case where that happens, feel free to start a thread here on DevForums. See the top of this post for info on the topic and tags to use. Note Prior to the Feb 2025 change, things generally worked out fine when you app was deployed but you might’ve run into problems during development. That’s no longer the case. [1] This is what allows Mac Catalyst and iOS Apps on Mac to work. Revision History 2025-08-12 Added a reference to the Register App Groups build setting. 2025-07-28 Updated the Crossing the Streams section for the Jun 2025 change. Made other minor editorial changes. 2025-04-16 Rewrote the document now that iOS-style app group IDs are fully supported on the Mac. Changed the title from App Groups: macOS vs iOS: Fight! to App Groups: macOS vs iOS: Working Towards Harmony 2025-02-25 Fixed the Xcode version number mentioned in yesterday’s update. 2025-02-24 Added a quick update about the iOS-style app group IDs on macOS issue. 2024-11-05 Further clarified app group container protection. Reworked some other sections to account for this new reality. 2024-10-29 Clarified the points in App Group Container Protection. 2024-10-23 Fleshed out the discussion of app group container protection on macOS 15. 2024-09-04 Added information about app group container protection on macOS 15. 2023-01-31 Renamed the Not Entirely Unsatisfactory section to Not Entirely Unsatisfied. Updated it to describe the real impact of that log message. 2022-12-12 First posted.