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217 lines
13 KiB
Markdown
217 lines
13 KiB
Markdown
# MacOS MDM
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## MacOS MDM
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<details>
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<summary><strong>Support HackTricks and get benefits!</strong></summary>
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* Do you work in a **cybersecurity company**? Do you want to see your **company advertised in HackTricks**? or do you want to have access to the **latest version of the PEASS or download HackTricks in PDF**? Check the [**SUBSCRIPTION PLANS**](https://github.com/sponsors/carlospolop)!
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* Discover [**The PEASS Family**](https://opensea.io/collection/the-peass-family), our collection of exclusive [**NFTs**](https://opensea.io/collection/the-peass-family)
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* Get the [**official PEASS & HackTricks swag**](https://peass.creator-spring.com)
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* **Join the** [**💬**](https://emojipedia.org/speech-balloon/) [**Discord group**](https://discord.gg/hRep4RUj7f) or the [**telegram group**](https://t.me/peass) or **follow** me on **Twitter** [**🐦**](https://github.com/carlospolop/hacktricks/tree/7af18b62b3bdc423e11444677a6a73d4043511e9/\[https:/emojipedia.org/bird/README.md)[**@carlospolopm**](https://twitter.com/carlospolopm)**.**
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* **Share your hacking tricks by submitting PRs to the** [**hacktricks github repo**](https://github.com/carlospolop/hacktricks)**.**
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</details>
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## Basics
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### What is MDM (Mobile Device Management)?
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[Mobile Device Management](https://en.wikipedia.org/wiki/Mobile\_device\_management) (MDM) is a technology commonly used to **administer end-user computing devices** such as mobile phones, laptops, desktops and tablets. In the case of Apple platforms like iOS, macOS and tvOS, it refers to a specific set of features, APIs and techniques used by administrators to manage these devices. Management of devices via MDM requires a compatible commercial or open-source MDM server that implements support for the [MDM Protocol](https://developer.apple.com/enterprise/documentation/MDM-Protocol-Reference.pdf).
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* A way to achieve **centralized device management**
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* Requires an **MDM server** which implements support for the MDM protocol
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* MDM server can **send MDM commands**, such as remote wipe or “install this config”
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### Basics What is DEP (Device Enrolment Program)?
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The [Device Enrollment Program](https://www.apple.com/business/site/docs/DEP\_Guide.pdf) (DEP) is a service offered by Apple that **simplifies** Mobile Device Management (MDM) **enrollment** by offering **zero-touch configuration** of iOS, macOS, and tvOS devices. Unlike more traditional deployment methods, which require the end-user or administrator to take action to configure a device, or manually enroll with an MDM server, DEP aims to bootstrap this process, **allowing the user to unbox a new Apple device and have it configured for use in the organization almost immediately**.
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Administrators can leverage DEP to automatically enroll devices in their organization’s MDM server. Once a device is enrolled, **in many cases it is treated as a “trusted”** device owned by the organization, and could receive any number of certificates, applications, WiFi passwords, VPN configurations [and so on](https://developer.apple.com/enterprise/documentation/Configuration-Profile-Reference.pdf).
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* Allows a device to automatically enroll in pre-configured MDM server the **first time it’s powered** on
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* Most useful when the **device** is **brand new**
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* Can also be useful for **reprovisioning** workflows (**wiped** with fresh install of the OS)
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{% hint style="danger" %}
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Unfortunately, if an organization has not taken additional steps to **protect their MDM enrollment**, a simplified end-user enrollment process through DEP can also mean a simplified process for **attackers to enroll a device of their choosing in the organization’s MDM** server, assuming the "identity" of a corporate device.
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{% endhint %}
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### Basics What is SCEP (Simple Certificate Enrolment Protocol)?
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* A relatively old protocol, created before TLS and HTTPS were widespread.
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* Gives clients a standardized way of sending a **Certificate Signing Request** (CSR) for the purpose of being granted a certificate. The client will ask the server to give him a signed certificate.
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### What are Configuration Profiles (aka mobileconfigs)?
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* Apple’s official way of **setting/enforcing system configuration.**
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* File format that can contain multiple payloads.
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* Based on property lists (the XML kind).
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* “can be signed and encrypted to validate their origin, ensure their integrity, and protect their contents.” Basics — Page 70, iOS Security Guide, January 2018.
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## Protocols
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### MDM
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* Combination of APNs (**Apple server**s) + RESTful API (**MDM** **vendor** servers)
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* **Communication** occurs between a **device** and a server associated with a **device** **management** **product**
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* **Commands** delivered from the MDM to the device in **plist-encoded dictionaries**
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* All over **HTTPS**. MDM servers can be (and are usually) pinned.
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* Apple grants the MDM vendor an **APNs certificate** for authentication
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### DEP
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* **3 APIs**: 1 for resellers, 1 for MDM vendors, 1 for device identity (undocumented):
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* The so-called [DEP "cloud service" API](https://developer.apple.com/enterprise/documentation/MDM-Protocol-Reference.pdf). This is used by MDM servers to associate DEP profiles with specific devices.
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* The [DEP API used by Apple Authorized Resellers](https://applecareconnect.apple.com/api-docs/depuat/html/WSImpManual.html) to enroll devices, check enrollment status, and check transaction status.
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* The undocumented private DEP API. This is used by Apple Devices to request their DEP profile. On macOS, the `cloudconfigurationd` binary is responsible for communicating over this API.
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* More modern and **JSON** based (vs. plist)
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* Apple grants an **OAuth token** to the MDM vendor
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**DEP "cloud service" API**
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* RESTful
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* sync device records from Apple to the MDM server
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* sync “DEP profiles” to Apple from the MDM server (delivered by Apple to the device later on)
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* A DEP “profile” contains:
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* MDM vendor server URL
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* Additional trusted certificates for server URL (optional pinning)
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* Extra settings (e.g. which screens to skip in Setup Assistant)
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## Steps for enrolment and management
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1. Device record creation (Reseller, Apple): The record for the new device is created
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2. Device record assignment (Customer): The device is assigned to a MDM server
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3. Device record sync (MDM vendor): MDM sync the device records and push the DEP profiles to Apple
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4. DEP check-in (Device): Device gets his DEP profile
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5. Profile retrieval (Device)
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6. Profile installation (Device) a. incl. MDM, SCEP and root CA payloads
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7. MDM command issuance (Device)
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.png>)
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The file `/Library/Developer/CommandLineTools/SDKs/MacOSX10.15.sdk/System/Library/PrivateFrameworks/ConfigurationProfiles.framework/ConfigurationProfiles.tbd` exports functions that can be considered **high-level "steps"** of the enrolment process.
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### Step 4: DEP check-in - Getting the Activation Record
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This part of the process occurs when a **user boots a Mac for the first time** (or after a complete wipe)
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.png>)
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or when executing `sudo profiles show -type enrollment`
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* Determine **whether device is DEP enabled**
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* Activation Record is the internal name for **DEP “profile”**
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* Begins as soon as the device is connected to Internet
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* Driven by **`CPFetchActivationRecord`**
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* Implemented by **`cloudconfigurationd`** via XPC. The **"Setup Assistant**" (when the device is firstly booted) or the **`profiles`** command will **contact this daemon** to retrieve the activation record.
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* LaunchDaemon (always runs as root)
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It follows a few steps to get the Activation Record performed by **`MCTeslaConfigurationFetcher`**. This process uses an encryption called **Absinthe**
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1. Retrieve **certificate**
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1. GET [https://iprofiles.apple.com/resource/certificate.cer](https://iprofiles.apple.com/resource/certificate.cer)
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2. **Initialize** state from certificate (**`NACInit`**)
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1. Uses various device-specific data (i.e. **Serial Number via `IOKit`**)
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3. Retrieve **session key**
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1. POST [https://iprofiles.apple.com/session](https://iprofiles.apple.com/session)
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4. Establish the session (**`NACKeyEstablishment`**)
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5. Make the request
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1. POST to [https://iprofiles.apple.com/macProfile](https://iprofiles.apple.com/macProfile) sending the data `{ "action": "RequestProfileConfiguration", "sn": "" }`
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2. The JSON payload is encrypted using Absinthe (**`NACSign`**)
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3. All requests over HTTPs, built-in root certificates are used
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 (1).png>)
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The response is a JSON dictionary with some important data like:
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* **url**: URL of the MDM vendor host for the activation profile
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* **anchor-certs**: Array of DER certificates used as trusted anchors
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### **Step 5: Profile Retrieval**
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.png>)
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* Request sent to **url provided in DEP profile**.
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* **Anchor certificates** are used to **evaluate trust** if provided.
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* Reminder: the **anchor\_certs** property of the DEP profile
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* **Request is a simple .plist** with device identification
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* Examples: **UDID, OS version**.
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* CMS-signed, DER-encoded
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* Signed using the **device identity certificate (from APNS)**
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* **Certificate chain** includes expired **Apple iPhone Device CA**
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 (1) (2) (2) (2) (2) (2) (2) (2) (1) (1) (1) (1) (1) (1) (1) (1) (1) (1) (1) (1) (1) (1) (1) (1) (1) (1) (1) (1) (1) (1) (1) (1) (1) (1) (1) (2) (1).png>)
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### Step 6: Profile Installation
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* Once retrieved, **profile is stored on the system**
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* This step begins automatically (if in **setup assistant**)
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* Driven by **`CPInstallActivationProfile`**
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* Implemented by mdmclient over XPC
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* LaunchDaemon (as root) or LaunchAgent (as user), depending on context
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* Configuration profiles have multiple payloads to install
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* Framework has a plugin-based architecture for installing profiles
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* Each payload type is associated with a plugin
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* Can be XPC (in framework) or classic Cocoa (in ManagedClient.app)
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* Example:
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* Certificate Payloads use CertificateService.xpc
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Typically, **activation profile** provided by an MDM vendor will **include the following payloads**:
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* `com.apple.mdm`: to **enroll** the device in MDM
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* `com.apple.security.scep`: to securely provide a **client certificate** to the device.
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* `com.apple.security.pem`: to **install trusted CA certificates** to the device’s System Keychain.
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* Installing the MDM payload equivalent to **MDM check-in in the documentation**
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* Payload **contains key properties**:
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*
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* MDM Check-In URL (**`CheckInURL`**)
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* MDM Command Polling URL (**`ServerURL`**) + APNs topic to trigger it
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* To install MDM payload, request is sent to **`CheckInURL`**
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* Implemented in **`mdmclient`**
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* MDM payload can depend on other payloads
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* Allows **requests to be pinned to specific certificates**:
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* Property: **`CheckInURLPinningCertificateUUIDs`**
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* Property: **`ServerURLPinningCertificateUUIDs`**
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* Delivered via PEM payload
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* Allows device to be attributed with an identity certificate:
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* Property: IdentityCertificateUUID
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* Delivered via SCEP payload
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### **Step 7: Listening for MDM commands**
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* After MDM check-in is complete, vendor can **issue push notifications using APNs**
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* Upon receipt, handled by **`mdmclient`**
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* To poll for MDM commands, request is sent to ServerURL
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* Makes use of previously installed MDM payload:
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* **`ServerURLPinningCertificateUUIDs`** for pinning request
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* **`IdentityCertificateUUID`** for TLS client certificate
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## Attacks
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### Enrolling Devices in Other Organisations
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As previously commented, in order to try to enrol a device into an organization **only a Serial Number belonging to that Organization is needed**. Once the device is enrolled, several organizations will install sensitive data on the new device: certificates, applications, WiFi passwords, VPN configurations [and so on](https://developer.apple.com/enterprise/documentation/Configuration-Profile-Reference.pdf).\
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Therefore, this could be a dangerous entrypoint for attackers if the enrolment process isn't correctly protected:
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{% content-ref url="enrolling-devices-in-other-organisations.md" %}
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[enrolling-devices-in-other-organisations.md](enrolling-devices-in-other-organisations.md)
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{% endcontent-ref %}
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## **References**
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* [https://www.youtube.com/watch?v=ku8jZe-MHUU](https://www.youtube.com/watch?v=ku8jZe-MHUU)
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* [https://duo.com/labs/research/mdm-me-maybe](https://duo.com/labs/research/mdm-me-maybe)
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<details>
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<summary><strong>Support HackTricks and get benefits!</strong></summary>
|
||
|
||
* Do you work in a **cybersecurity company**? Do you want to see your **company advertised in HackTricks**? or do you want to have access to the **latest version of the PEASS or download HackTricks in PDF**? Check the [**SUBSCRIPTION PLANS**](https://github.com/sponsors/carlospolop)!
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||
* Discover [**The PEASS Family**](https://opensea.io/collection/the-peass-family), our collection of exclusive [**NFTs**](https://opensea.io/collection/the-peass-family)
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||
* Get the [**official PEASS & HackTricks swag**](https://peass.creator-spring.com)
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* **Join the** [**💬**](https://emojipedia.org/speech-balloon/) [**Discord group**](https://discord.gg/hRep4RUj7f) or the [**telegram group**](https://t.me/peass) or **follow** me on **Twitter** [**🐦**](https://github.com/carlospolop/hacktricks/tree/7af18b62b3bdc423e11444677a6a73d4043511e9/\[https:/emojipedia.org/bird/README.md)[**@carlospolopm**](https://twitter.com/carlospolopm)**.**
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* **Share your hacking tricks by submitting PRs to the** [**hacktricks github repo**](https://github.com/carlospolop/hacktricks)**.**
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</details>
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