I regularly help developers with keychain problems, both here on DevForums and for my Day Job™ in DTS. Many of these problems are caused by a fundamental misunderstanding of how the keychain works. This post is my attempt to explain that. I wrote it primarily so that Future Quinn™ can direct folks here rather than explain everything from scratch (-: If you have questions or comments about any of this, put them in a new thread and apply the Security tag so that I see it. Share and Enjoy — Quinn “The Eskimo!” @ Developer Technical Support @ Apple let myEmail = "eskimo" + "1" + "@" + "apple.com" SecItem: Fundamentals or How I Learned to Stop Worrying and Love the SecItem API The SecItem API seems very simple. After all, it only has four function calls, how hard can it be? In reality, things are not that easy. Various factors contribute to making this API much trickier than it might seem at first glance. This post explains the fundamental underpinnings of the keychain. For information about specific issues, see its companion post, SecItem: Pitfalls and Best Practices. Keychain Documentation Your basic starting point should be Keychain Items. If your code runs on the Mac, also read TN3137 On Mac keychain APIs and implementations. Read the doc comments in <Security/SecItem.h>. In many cases those doc comments contain critical tidbits. When you read keychain documentation [1] and doc comments, keep in mind that statements specific to iOS typically apply to iPadOS, tvOS, and watchOS as well (r. 102786959). Also, they typically apply to macOS when you target the data protection keychain. Conversely, statements specific to macOS may not apply when you target the data protection keychain. [1] Except TN3137, which is very clear about this (-: Caveat Mac Developer macOS supports two different keychain implementations: the original file-based keychain and the iOS-style data protection keychain. IMPORTANT If you’re able to use the data protection keychain, do so. It’ll make your life easier. See the Careful With that Shim, Mac Developer section of SecItem: Pitfalls and Best Practices for more about this. TN3137 On Mac keychain APIs and implementations explains this distinction. It also says: The file-based keychain is on the road to deprecation. This is talking about the implementation, not any specific API. The SecItem API can’t be deprecated because it works with both the data protection keychain and the file-based keychain. However, Apple has deprecated many APIs that are specific to the file-based keychain, for example, SecKeychainCreate. TN3137 also notes that some programs, like launchd daemons, can’t use the file-based keychain. If you’re working on such a program then you don’t have to worry about the deprecation of these file-based keychain APIs. You’re already stuck with the file-based keychain implementation, so using a deprecated file-based keychain API doesn’t make things worse. The Four Freedoms^H^H^H^H^H^H^H^H Functions The SecItem API contains just four functions: SecItemAdd(_:_:) SecItemCopyMatching(_:_:) SecItemUpdate(_:_:) SecItemDelete(_:) These directly map to standard SQL database operations: SecItemAdd(_:_:) maps to INSERT. SecItemCopyMatching(_:_:) maps to SELECT. SecItemUpdate(_:_:) maps to UPDATE. SecItemDelete(_:) maps to DELETE. You can think of each keychain item class (generic password, certificate, and so on) as a separate SQL table within the database. The rows of that table are the individual keychain items for that class and the columns are the attributes of those items. Note Except for the digital identity class, kSecClassIdentity, where the values are split across the certificate and key tables. See Digital Identities Aren’t Real in SecItem: Pitfalls and Best Practices. This is not an accident. The data protection keychain is actually implemented as an SQLite database. If you’re curious about its structure, examine it on the Mac by pointing your favourite SQLite inspection tool — for example, the sqlite3 command-line tool — at the keychain database in ~/Library/Keychains/UUU/keychain-2.db, where UUU is a UUID. WARNING Do not depend on the location and structure of this file. These have changed in the past and are likely to change again in the future. If you embed knowledge of them into a shipping product, it’s likely that your product will have binary compatibility problems at some point in the future. The only reason I’m mentioning them here is because I find it helpful to poke around in the file to get a better understanding of how the API works. For information about which attributes are supported by each keychain item class — that is, what columns are in each table — see the Note box at the top of Item Attribute Keys and Values. Alternatively, look at the Attribute Key Constants doc comment in <Security/SecItem.h>. Uniqueness A critical part of the keychain model is uniqueness. How does the keychain determine if item A is the same as item B? It turns out that this is class dependent. For each keychain item class there is a set of attributes that form the uniqueness constraint for items of that class. That is, if you try to add item A where all of its attributes are the same as item B, the add fails with errSecDuplicateItem. For more information, see the errSecDuplicateItem page. It has lists of attributes that make up this uniqueness constraint, one for each class. These uniqueness constraints are a major source of confusion, as discussed in the Queries and the Uniqueness Constraints section of SecItem: Pitfalls and Best Practices. Parameter Blocks Understanding The SecItem API is a classic ‘parameter block’ API. All of its inputs are dictionaries, and you have to know which properties to set in each dictionary to achieve your desired result. Likewise for when you read properties in output dictionaries. There are five different property groups: The item class property, kSecClass, determines the class of item you’re operating on: kSecClassGenericPassword, kSecClassCertificate, and so on. The item attribute properties, like kSecAttrAccessGroup, map directly to keychain item attributes. The search properties, like kSecMatchLimit, control how the system runs a query. The return type properties, like kSecReturnAttributes, determine what values the query returns. The value type properties, like kSecValueRef perform multiple duties, as explained below. There are other properties that perform a variety of specific functions. For example, kSecUseDataProtectionKeychain tells macOS to use the data protection keychain instead of the file-based keychain. These properties are hard to describe in general; for the details, see the documentation for each such property. Inputs Each of the four SecItem functions take dictionary input parameters of the same type, CFDictionary, but these dictionaries are not the same. Different dictionaries support different property groups: The first parameter of SecItemAdd(_:_:) is an add dictionary. It supports all property groups except the search properties. The first parameter of SecItemCopyMatching(_:_:) is a query and return dictionary. It supports all property groups. The first parameter of SecItemUpdate(_:_:) is a pure query dictionary. It supports all property groups except the return type properties. Likewise for the only parameter of SecItemDelete(_:). The second parameter of SecItemUpdate(_:_:) is an update dictionary. It supports the item attribute and value type property groups. Outputs Two of the SecItem functions, SecItemAdd(_:_:) and SecItemCopyMatching(_:_:), return values. These output parameters are of type CFTypeRef because the type of value you get back depends on the return type properties you supply in the input dictionary: If you supply a single return type property, except kSecReturnAttributes, you get back a value appropriate for that return type. If you supply multiple return type properties or kSecReturnAttributes, you get back a dictionary. This supports the item attribute and value type property groups. To get a non-attribute value from this dictionary, use the value type property that corresponds to its return type property. For example, if you set kSecReturnPersistentRef in the input dictionary, use kSecValuePersistentRef to get the persistent reference from the output dictionary. In the single item case, the type of value you get back depends on the return type property and the keychain item class: For kSecReturnData you get back the keychain item’s data. This makes most sense for password items, where the data holds the password. It also works for certificate items, where you get back the DER-encoded certificate. Using this for key items is kinda sketchy. If you want to export a key, called SecKeyCopyExternalRepresentation. Using this for digital identity items is nonsensical. For kSecReturnRef you get back an object reference. This only works for keychain item classes that have an object representation, namely certificates, keys, and digital identities. You get back a SecCertificate, a SecKey, or a SecIdentity, respectively. For kSecReturnPersistentRef you get back a data value that holds the persistent reference. Value Type Subtleties There are three properties in the value type property group: kSecValueData kSecValueRef kSecValuePersistentRef Their semantics vary based on the dictionary type. For kSecValueData: In an add dictionary, this is the value of the item to add. For example, when adding a generic password item (kSecClassGenericPassword), the value of this key is a Data value containing the password. This is not supported in a query dictionary. In an update dictionary, this is the new value for the item. For kSecValueRef: In add and query dictionaries, the system infers the class property and attribute properties from the supplied object. For example, if you supply a certificate object (SecCertificate, created using SecCertificateCreateWithData), the system will infer a kSecClass value of kSecClassCertificate and various attribute values, like kSecAttrSerialNumber, from that certificate object. This is not supported in an update dictionary. For kSecValuePersistentRef: For query dictionaries, this uniquely identifies the item to operate on. This is not supported in add and update dictionaries. Revision History 2025-05-28 Expanded the Caveat Mac Developer section to cover some subtleties associated with the deprecation of the file-based keychain. 2023-09-12 Fixed various bugs in the revision history. Added a paragraph explaining how to determine which attributes are supported by each keychain item class. 2023-02-22 Made minor editorial changes. 2023-01-28 First posted.

When trying to check if a certificate has been revoked with SecPolicyCreateRevocation (Flags: kSecRevocationUseAnyAvailableMethod | kSecRevocationRequirePositiveResponse) and SecTrustEvaluateWithError I always get the result error code errSecIncompleteCertRevocationCheck, regardless if the certificate was revoked or not. Reproduction: Execute the program from the attached Xcode project (See Feedback FB21224106). Error output: Error: Error Domain=NSOSStatusErrorDomain Code=-67635 ""revoked.badssl.com","E8","ISRG Root X1" certificates do not meet pinning requirements" UserInfo={NSLocalizedDescription="revoked.badssl.com","E8","ISRG Root X1" certificates do not meet pinning requirements, NSUnderlyingError=0x6000018d48a0 {Error Domain=NSOSStatusErrorDomain Code=-67635 "Certificate 0 “revoked.badssl.com” has errors: Failed to check revocation;" UserInfo={NSLocalizedDescription=Certificate 0 “revoked.badssl.com” has errors: Failed to check revocation;}}} To me it looks like that the revocation check just fails („Failed to check revocation;“), no further information is provided by the returned error. In the example the certificate chain of https://revoked.badssl.com (default code) and https://badssl.com is verified (to switch see comments in the code). I have a proxy configured in the system, I assume that the revocation check will use it. On the same machine, the browsers (Safari and Google Chrome) can successfully detect if the certificate was revoked (revoked.badssl.com) or not (badssl.com) without further changes in the system/proxy settings. Note: The example leaks some memory, it’s just a test program. Am I missing something? Feedback: FB21224106

Hi, We are trying to use Apple Security API for KeyChain Services. Using the common App Group : Specifying the common app group in the "kSecAttrAccessGroup" field of the KeyChain query, allowed us to have a shared keychains for different apps (targets) in the app group, but this did not work for extensions. Enabling the KeyChain Sharing capability : We enabled the KeyChain Sharing Ability in the extensions and the app target as well, giving a common KeyChain Access group. Specifying this in the kSecAttrAccessGroup field also did not work. This was done in XCode as we were unable to locate it in the Developer portal in Indentifiers. We tried specifying "$AppIdentifier.KeyChainSharingGroup" in the kSecAttrAccessGroup field , but this did not work as well The error code which we get in all these 3 cases when trying to access the Keychain from the extension is error code 25291 (errSecNotAvailable). The Documentation says this error comes when "No Trust Results are available" and printing the error in xcode using the status says "No keychain is available. The online Documentation says that it is possible to share keychain with extensions, but by far we are unable to do it with the methods suggested. Do we need any special entitlement for this or is there something we are missing while using these APIs? We really appreciate any and all help in solving this issue! Thank you

Hello, We are facing an issue with performing a DTLS handshake when our iOS application is in the background. Our app (Vocera Collaboration Suite – VCS) uses secure DTLS-encrypted communication for incoming VoIP calls. Problem Summary: When the app is in the background and a VoIP PushKit notification arrives, we attempt to establish a DTLS handshake over our existing socket. However, the handshake consistently fails unless the app is already in the foreground. Once the app is foregrounded, the same DTLS handshake logic succeeds immediately. Key Questions: Is performing a DTLS handshake while the app is in the background technically supported by iOS? Or is this an OS-level limitation by design? If not supported, what is the Apple-recommended alternative to establish secure DTLS communication for VoIP flows without bringing the app to the foreground? Any guidance or clarification from Apple engineers or anyone who has solved a similar problem would be greatly appreciated. Thank you.

While working with Platform SSO on macOS, I’m trying to better understand how the system handles cases where a user’s local account password becomes unsynchronized with their Identity Provider (IdP) password—for example, when the device is offline during a password change. My assumption is that macOS may store some form of persistent token during the Platform SSO user registration process (such as a certificate or similar credential), and that this token could allow the system to unlock the user’s login keychain even if the local password no longer matches the IdP password. I’m hoping to get clarification on the following: Does macOS actually use a persistent token to unlock the login keychain when the local account password is out of sync with the IdP password? If so, how is that mechanism designed to work? If such a capability exists, is it something developers can leverage to enable a true passwordless authentication experience at the login window and lock screen (i.e., avoiding the need for a local password fallback)? I’m trying to confirm what macOS officially supports so I can understand whether passwordless login is achievable using the persistent-token approach. Thanks in advance for any clarification.

When I try to archive an app in order to submit it to the App Store I receive the following errors I do not know how to fix: error: Framework /Users/fbartolom/Library/Developer/Xcode/DerivedData/Virtual_Tags-apzduassdiglhcapscsllvzbfgid/Build/Intermediates.noindex/ArchiveIntermediates/Virtual Tags/InstallationBuildProductsLocation/Applications/VirtualTags.app/Frameworks/StoreKit.framework did not contain an Info.plist (in target 'VirtualTags' from project 'Virtual Tags') error: Framework /Users/fbartolom/Library/Developer/Xcode/DerivedData/Virtual_Tags-apzduassdiglhcapscsllvzbfgid/Build/Intermediates.noindex/ArchiveIntermediates/Virtual Tags/InstallationBuildProductsLocation/Applications/VirtualTags.app/Frameworks/Security.framework did not contain an Info.plist (in target 'VirtualTags' from project 'Virtual Tags') error: Framework /Users/fbartolom/Library/Developer/Xcode/DerivedData/Virtual_Tags-apzduassdiglhcapscsllvzbfgid/Build/Intermediates.noindex/ArchiveIntermediates/Virtual Tags/InstallationBuildProductsLocation/Applications/VirtualTags.app/Frameworks/CloudKit.framework did not contain an Info.plist (in target 'VirtualTags' from project 'Virtual Tags') MacBook Pro M5, Tahoe 26.1, Xcode 26.1.1

We have a custom SecurityAgentPlugin that is triggered by multiple authorizationdb entries. Some customers report that the SecurityAgent process takes window focus even though no UI or windows are displayed. Our plugin explicitly ignores the _securityAgent user and does not show any UI for that user. However, in macOS 26.1, it appears that the plugin still causes the SecurityAgent to take focus as soon as it is triggered. Is this a change in macOS 26.1 or a bug? Can we do anything to prevent "focus stealing"?

Hi, After enabling the new Enhanced Security capability in Xcode 26, I’m seeing install failures on devices running < iOS 26. Deployment target: iOS 15.0 Capability: Enhanced Security (added via Signing & Capabilities tab) Building to iOS 18 device error - Unable to Install ...Please ensure sure that your app is signed by a valid provisioning profile. It works fine on iOS 26 devices. I’d like to confirm Apple’s intent here: Is this capability formally supported only on iOS 26 and later, and therefore incompatible with earlier OS versions? Or should older systems ignore the entitlement, meaning this behavior might be a bug?

Transport Layer Security (TLS) is the most important security protocol on the Internet today. Most notably, TLS puts the S into HTTPS, adding security to the otherwise insecure HTTP protocol. IMPORTANT TLS is the successor to the Secure Sockets Layer (SSL) protocol. SSL is no longer considered secure and it’s now rarely used in practice, although many folks still say SSL when they mean TLS. TLS is a complex protocol. Much of that complexity is hidden from app developers but there are places where it’s important to understand specific details of the protocol in order to meet your requirements. This post explains the fundamentals of TLS, concentrating on the issues that most often confuse app developers. Note The focus of this is TLS-PKI, where PKI stands for public key infrastructure. This is the standard TLS as deployed on the wider Internet. There’s another flavour of TLS, TLS-PSK, where PSK stands for pre-shared key. This has a variety of uses, but an Apple platforms we most commonly see it with local traffic, for example, to talk to a Wi-Fi based accessory. For more on how to use TLS, both TLS-PKI and TLS-PSK, in a local context, see TLS For Accessory Developers. Server Certificates For standard TLS to work the server must have a digital identity, that is, the combination of a certificate and the private key matching the public key embedded in that certificate. TLS Crypto Magic™ ensures that: The client gets a copy of the server’s certificate. The client knows that the server holds the private key matching the public key in that certificate. In a typical TLS handshake the server passes the client a list of certificates, where item 0 is the server’s certificate (the leaf certificate), item N is (optionally) the certificate of the certificate authority that ultimately issued that certificate (the root certificate), and items 1 through N-1 are any intermediate certificates required to build a cryptographic chain of trust from 0 to N. Note The cryptographic chain of trust is established by means of digital signatures. Certificate X in the chain is issued by certificate X+1. The owner of certificate X+1 uses their private key to digitally sign certificate X. The client verifies this signature using the public key embedded in certificate X+1. Eventually this chain terminates in a trusted anchor, that is, a certificate that the client trusts by default. Typically this anchor is a self-signed root certificate from a certificate authority. Note Item N is optional for reasons I’ll explain below. Also, the list of intermediate certificates may be empty (in the case where the root certificate directly issued the leaf certificate) but that’s uncommon for servers in the real world. Once the client gets the server’s certificate, it evaluates trust on that certificate to confirm that it’s talking to the right server. There are three levels of trust evaluation here: Basic X.509 trust evaluation checks that there’s a cryptographic chain of trust from the leaf through the intermediates to a trusted root certificate. The client has a set of trusted root certificates built in (these are from well-known certificate authorities, or CAs), and a site admin can add more via a configuration profile. This step also checks that none of the certificates have expired, and various other more technical criteria (like the Basic Constraints extension). Note This explains why the server does not have to include the root certificate in the list of certificates it passes to the client; the client has to have the root certificate installed if trust evaluation is to succeed. In addition, TLS trust evaluation (per RFC 2818) checks that the DNS name that you connected to matches the DNS name in the certificate. Specifically, the DNS name must be listed in the Subject Alternative Name extension. Note The Subject Alternative Name extension can also contain IP addresses, although that’s a much less well-trodden path. Also, historically it was common to accept DNS names in the Common Name element of the Subject but that is no longer the case on Apple platforms. App Transport Security (ATS) adds its own security checks. Basic X.509 and TLS trust evaluation are done for all TLS connections. ATS is only done on TLS connections made by URLSession and things layered on top URLSession (like WKWebView). In many situations you can override trust evaluation; for details, see Technote 2232 HTTPS Server Trust Evaluation). Such overrides can either tighten or loosen security. For example: You might tighten security by checking that the server certificate was issued by a specific CA. That way, if someone manages to convince a poorly-managed CA to issue them a certificate for your server, you can detect that and fail. You might loosen security by adding your own CA’s root certificate as a trusted anchor. IMPORTANT If you rely on loosened security you have to disable ATS. If you leave ATS enabled, it requires that the default server trust evaluation succeeds regardless of any customisations you do. Mutual TLS The previous section discusses server trust evaluation, which is required for all standard TLS connections. That process describes how the client decides whether to trust the server. Mutual TLS (mTLS) is the opposite of that, that is, it’s the process by which the server decides whether to trust the client. Note mTLS is commonly called client certificate authentication. I avoid that term because of the ongoing industry-wide confusion between certificates and digital identities. While it’s true that, in mTLS, the server authenticates the client certificate, to set this up on the client you need a digital identity, not a certificate. mTLS authentication is optional. The server must request a certificate from the client and the client may choose to supply one or not (although if the server requests a certificate and the client doesn’t supply one it’s likely that the server will then fail the connection). At the TLS protocol level this works much like it does with the server certificate. For the client to provide this certificate it must apply a digital identity, known as the client identity, to the connection. TLS Crypto Magic™ assures the server that, if it gets a certificate from the client, the client holds the private key associated with that certificate. Where things diverge is in trust evaluation. Trust evaluation of the client certificate is done on the server, and the server uses its own rules to decided whether to trust a specific client certificate. For example: Some servers do basic X.509 trust evaluation and then check that the chain of trust leads to one specific root certificate; that is, a client is trusted if it holds a digital identity whose certificate was issued by a specific CA. Some servers just check the certificate against a list of known trusted client certificates. When the client sends its certificate to the server it actually sends a list of certificates, much as I’ve described above for the server’s certificates. In many cases the client only needs to send item 0, that is, its leaf certificate. That’s because: The server already has the intermediate certificates required to build a chain of trust from that leaf to its root. There’s no point sending the root, as I discussed above in the context of server trust evaluation. However, there are no hard and fast rules here; the server does its client trust evaluation using its own internal logic, and it’s possible that this logic might require the client to present intermediates, or indeed present the root certificate even though it’s typically redundant. If you have problems with this, you’ll have to ask the folks running the server to explain its requirements. Note If you need to send additional certificates to the server, pass them to the certificates parameter of the method you use to create your URLCredential (typically init(identity:certificates:persistence:)). One thing that bears repeating is that trust evaluation of the client certificate is done on the server, not the client. The client doesn’t care whether the client certificate is trusted or not. Rather, it simply passes that certificate the server and it’s up to the server to make that decision. When a server requests a certificate from the client, it may supply a list of acceptable certificate authorities [1]. Safari uses this to filter the list of client identities it presents to the user. If you are building an HTTPS server and find that Safari doesn’t show the expected client identity, make sure you have this configured correctly. If you’re building an iOS app and want to implement a filter like Safari’s, get this list using: The distinguishedNames property, if you’re using URLSession The sec_protocol_metadata_access_distinguished_names routine, if you’re using Network framework [1] See the certificate_authorities field in Section 7.4.4 of RFC 5246, and equivalent features in other TLS versions. Self-Signed Certificates Self-signed certificates are an ongoing source of problems with TLS. There’s only one unequivocally correct place to use a self-signed certificate: the trusted anchor provided by a certificate authority. One place where a self-signed certificate might make sense is in a local environment, that is, securing a connection between peers without any centralised infrastructure. However, depending on the specific circumstances there may be a better option. TLS For Accessory Developers discusses this topic in detail. Finally, it’s common for folks to use self-signed certificates for testing. I’m not a fan of that approach. Rather, I recommend the approach described in QA1948 HTTPS and Test Servers. For advice on how to set that up using just your Mac, see TN2326 Creating Certificates for TLS Testing. TLS Standards RFC 6101 The Secure Sockets Layer (SSL) Protocol Version 3.0 (historic) RFC 2246 The TLS Protocol Version 1.0 RFC 4346 The Transport Layer Security (TLS) Protocol Version 1.1 RFC 5246 The Transport Layer Security (TLS) Protocol Version 1.2 RFC 8446 The Transport Layer Security (TLS) Protocol Version 1.3 RFC 4347 Datagram Transport Layer Security RFC 6347 Datagram Transport Layer Security Version 1.2 RFC 9147 The Datagram Transport Layer Security (DTLS) Protocol Version 1.3 Share and Enjoy — Quinn “The Eskimo!” @ Developer Technical Support @ Apple let myEmail = "eskimo" + "1" + "@" + "apple.com" Revision History: 2025-11-21 Clearly defined the terms TLS-PKI and TLS-PSK. 2024-03-19 Adopted the term mutual TLS in preference to client certificate authentication throughout, because the latter feeds into the ongoing certificate versus digital identity confusion. Defined the term client identity. Added the Self-Signed Certificates section. Made other minor editorial changes. 2023-02-28 Added an explanation mTLS acceptable certificate authorities. 2022-12-02 Added links to the DTLS RFCs. 2022-08-24 Added links to the TLS RFCs. Made other minor editorial changes. 2022-06-03 Added a link to TLS For Accessory Developers. 2021-02-26 Fixed the formatting. Clarified that ATS only applies to URLSession. Minor editorial changes. 2020-04-17 Updated the discussion of Subject Alternative Name to account for changes in the 2019 OS releases. Minor editorial updates. 2018-10-29 Minor editorial updates. 2016-11-11 First posted.

Hello, When using ASWebAuthenticationSession with an HTTPS callback URL (Universal Link), I receive the following error: Authorization error: The operation couldn't be completed. Application with identifier jp.xxxx.yyyy.dev is not associated with domain xxxx-example.go.link. Using HTTPS callbacks requires Associated Domains using the webcredentials service type for xxxx-example.go.link. I checked Apple’s official documentation but couldn’t find any clear statement that webcredentials is required when using HTTPS callbacks in ASWebAuthenticationSession. What I’d like to confirm: Is webcredentials officially required when using HTTPS as a callback URL with ASWebAuthenticationSession? If so, is there any official documentation or technical note that states this requirement? Environment iOS 18.6.2 Xcode 16.4 Any clarification or official references would be greatly appreciated. Thank you.

I spent the entire day debugging a network issue on my Apple Watch app, only to realize the problem isn't my code—it's Apple's inflexible design. The Context: I am building a generic MCP (Model Context Protocol) client for watchOS. The nature of this app is to allow users to input their own server URLs (e.g., a self-hosted endpoint, or public services like GitHub's MCP server) to interact with LLMs and tools. The Problem: When using standard URLSession to connect to widely trusted, public HTTPS endpoints (specifically GitHub's official MCP server at https://mcp.github.com), the connection is forcefully terminated by the OS with NSURLErrorDomain Code=-1200 (TLS handshake failed). The Analysis: This is caused by App Transport Security (ATS). ATS is enforcing a draconian set of security standards (specific ciphers, forward secrecy requirements, etc.) that many perfectly valid, secure, and globally accepted servers do not strictly meet 100%. The Absurdity: We cannot whitelist domains: Since this is a generic client, I cannot add NSExceptionDomains to Info.plist because I don't know what URL the user will input. We cannot disable ATS: Adding NSAllowsArbitraryLoads is a guaranteed rejection during App Store review for a general-purpose app without a "compelling reason" acceptable to Apple. The result: My app is effectively bricked. It cannot connect to GitHub. It cannot connect to 90% of the user's self-hosted servers. The Question: Is the Apple Watch just a toy? How does Apple expect us to build flexible, professional tools when the OS acts like a nanny that blocks connections to GitHub? We need a way to bypass strict ATS checks for user-initiated connections in generic network tools, similar to how curl -k or other developer tools work. The current "all-or-nothing" policy is suffocating.

I'm looking to implement USB monitoring for FIDO2 authentication through a custom Authorization Plugin, specifically for the below ones. This plugin applies to the following macOS authorization mechanisms: system.login.console — login window authentication system.login.screensaver — screensaver unlock authentication The goal is to build a GUI AuthPlugin, an authorization plugin that presents a custom window prompting the user to "Insert your FIDO key”. Additionally, the plugin should detect when the FIDO2 device is removed and respond accordingly. Additional Info: We have already developed a custom authorization plugin which is a primary authentication using OTP at login and Lock Screen. We are now extending to include FIDO2 support as a primary. Our custom authorization plugin is designed to replace the default loginwindow:login mechanism with a custom implementation. Question: Is there a reliable approach to achieve the USB monitoring functionality through a custom authorization plugin? Any guidance or pointers on this would be greatly appreciated.

I've had a Unreal Engine project that uses libwebsocket to make a websocket connection with SSL to a server. Recently I made a build using Unreal Engine 5.4.4 on MacOS Sequoia 15.5 and XCode 16.4 and for some reason the websocket connection now fails because it can't get the local issuer certificate. It fails to access the root certificate store on my device (Even though, running the project in the Unreal Editor works fine, it's only when making a packaged build with XCode that it breaks) I am not sure why this is suddenly happening now. If I run it in the Unreal editor on my macOS it works fine and connects. But when I make a packaged build which uses XCode to build, it can't get the local issuer certificate. I tried different code signing options, such as sign to run locally or just using sign automatically with a valid team, but I'm not sure if code signing is the cause of this issue or not. This app is only for development and not meant to be published, so that's why I had been using sign to run locally, and that used to work fine but not anymore. Any guidance would be appreciated, also any information on what may have changed that now causes this certificate issue to happen. I know Apple made changes and has made notarizing MacOS apps mandatory, but I'm not sure if that also means a non-notarized app will now no longer have access to the root certificate store of a device, in my research I haven't found anything about that specifically, but I'm wondering if any Apple engineers might know something about this that hasn't been put out publicly.

General: Forums topic: Privacy & Security Apple Platform Security support document Developer > Security Enabling enhanced security for your app documentation article Creating enhanced security helper extensions documentation article Security Audit Thoughts forums post Cryptography: Forums tags: Security, Apple CryptoKit Security framework documentation Apple CryptoKit framework documentation Common Crypto man pages — For the full list of pages, run: % man -k 3cc For more information about man pages, see Reading UNIX Manual Pages. On Cryptographic Key Formats forums post SecItem attributes for keys forums post CryptoCompatibility sample code Keychain: Forums tags: Security Security > Keychain Items documentation TN3137 On Mac keychain APIs and implementations SecItem Fundamentals forums post SecItem Pitfalls and Best Practices forums post Investigating hard-to-reproduce keychain problems forums post App ID Prefix Change and Keychain Access forums post Smart cards and other secure tokens: Forums tag: CryptoTokenKit CryptoTokenKit framework documentation Mac-specific resources: Forums tags: Security Foundation, Security Interface Security Foundation framework documentation Security Interface framework documentation BSD Privilege Escalation on macOS Related: Networking Resources — This covers high-level network security, including HTTPS and TLS. Network Extension Resources — This covers low-level network security, including VPN and content filters. Code Signing Resources Notarisation Resources Trusted Execution Resources — This includes Gatekeeper. App Sandbox Resources Share and Enjoy — Quinn “The Eskimo!” @ Developer Technical Support @ Apple let myEmail = "eskimo" + "1" + "@" + "apple.com"

It seems it is not possible to give a CLI app (non .app bundle) full disk access in macOS 26.1. This seems like a bug and if not that is a breaking change. Anybody seeing the same problem? Our application needs full disk access for a service running as a LaunchDaemon. The binary is located in a /Library subfolder.

I am trying to communicate with the backend of my project. So I need to install the certificate into the simulator. I have the .pem file but when I drag-dropped it into the simulator, I got the error "Simulator device failed to complete the requested operation.". The simulator is an iPhone 16 Pro running iOS 18.5. Is there any way to install the cert to my simulator? PS: I can't use Apple Configurator or MDM because I am using the office's Mac. And I can't install anything there. So I can only do it manually.

Hi everyone 👋 I’m running into a persistent SSL issue on iOS where the app fails to establish a secure HTTPS connection to our backend APIs. The same endpoints work fine on Android and web, but on iOS the requests fail with: Error Domain=NSURLErrorDomain Code=-1200 "An SSL error has occurred and a secure connection to the server cannot be made." UserInfo={ NSLocalizedDescription = "An SSL error has occurred and a secure connection to the server cannot be made."; _kCFStreamErrorDomainKey = 3; _kCFStreamErrorCodeKey = -9802; } 🔍 What I’ve Checked: The servers use valid, trusted SSL certificates from a public CA TLS 1.2 and 1.3 are enabled The intermediate certificates appear correctly configured (verified using SSL Labs) The issue happens on our customer's end. (Got it via Sentry) Note: We recently removed NSAppTransportSecurity(NSAllowsArbitraryLoads) on our app, since all the endpoints use valid HTTPS certificates and standard configurations. ❓ Questions: Are there additional SSL validation checks performed by iOS when ATS is enabled? Has anyone seen similar behaviour, where valid certificate chains still trigger SSL errors? Any insights or debugging suggestions would be greatly appreciated 🙏

Hi, I’ve developed a custom Authorization Plugin and placed it under: /Library/Security/SecurityAgentPlugins/AuthPlugin.bundle I also updated the corresponding right in the authorization database (authorizationdb) to point to my plugin’s mechanism. However, when I invoke the right, my plugin does not get loaded. The system log shows the following errors: AuthorizationHostHelper: Init: unable to load bundle executable for plugin: AuthPlugin.bundle AuthorizationHostHelper: Processing request: Failed to create agent mechanism AuthPlugin:auth.startup.authenticate, failing authentication! Here’s what I’ve verified so far: The plugin bundle and its executable are signed and notarized successfully. The executable inside the bundle is universal (arm64 + x86_64). The bundle structure looks correct (Contents/Info.plist, Contents/MacOS/..., etc.). Despite that, the plugin fails to load at runtime. Could anyone provide advice on how to debug or trace why the SecurityAgent cannot load the bundle executable? Are there any entitlements, permissions, or SIP-related restrictions that might prevent custom authorization plugins from being loaded on modern macOS versions? Thanks in advance for any insights!

Hello, Thanks for the new video on Memory Integrity Enforcement! Is the presented app's sample code available (so that we can play with it and find & fix the bug on our own, using Soft Mode)? Thanks in advance!

I have an swift command line tool that changes proxy settings in system preferences via SystemConfiguration framework, does some stuff, and in the end reverts proxy settings back to original. Here is simplified code: var authorization: AuthorizationRef? let status = AuthorizationCreate(nil, nil, [], &authorization) let prefs = SCPreferencesCreateWithAuthorization(nil, "myapp" as CFString, nil, authorization) // change proxy setttings // do some stuff let prefs2 = SCPreferencesCreateWithAuthorization(nil, "myapp" as CFString, nil, authorization) // change proxy settings back to original When I try to change settings for the first time, the system dialog appears requesting permission to change network settings. If I try to change settings again within а short period of time, the dialog does not appear again. However, if it takes more than several minutes after first change, the dialog does appear again. Is there a way to create authorization, so that the dialog appears only once per app launch, no matter how much time passed since the first dialog?