Android

Deploy certificates to Android devices via SCEP using Intune and SCEPman.

The following article describes how to deploy a device or a user certificate for Android. Android certificate deployment is similar to Windows 10, macOS, and iOS certificate deployments.

Android provides two distinct solution sets: one is the work profile (known as Personally-Owned Work Profile) and the other is the fully managed device (known also as Fully Managed, Dedicated, and Corporate-Owned Work Profile). In both scenarios, the settings for certificate configuration profiles remain consistent.

Android device administrator management was released in Android 2.2 as a way to manage Android devices. Then beginning with Android 5, the more modern management framework of Android Enterprise was released (for devices that can reliably connect to Google Mobile Services). Google is encouraging movement from device administrator management by decreasing its management support in new Android releases. For more information please check MS. Intune Decreasing support for Android device admin

Root Certificate

The basis for deploying SCEP certificates (device or user) is to trust the root certificate of SCEPman. Therefore, you have to download the CA Root certificate and deploy it as a Trusted certificate profile via Microsoft Intune:

• Download the CA Certificate from SCEPman portal

• Create a profile for Android Enterprise with the type Trusted certificate in Microsoft Intune (based on your enrollment option for Android devices)

• Upload your previously downloaded .cer file.

• Now you can deploy this profile to your devices. Please choose All Users and/or All Devices or a dedicated group for the assignment.

Note, that you have to use the same group for assigning the Trusted certificate and SCEP profile. Otherwise, the Intune deployment might fail.

Device Certificates

• Open the SCEPman portal and copy the URL under Intune MDM

• Create a profile for Android Enterprise with type SCEP certificate in Microsoft Intune (again, based on your enrollment option for the Android devices)

• Configure the profile as described

Certificate type: Device

In this section, we are setting up a device certificate.

Subject name format: CN={{DeviceId}} or CN={{AAD_Device_ID}}

SCEPman uses the CN field of the subject to identify the device and as a seed for the certificate serial number generation. Microsoft Entra ID (Azure AD) and Intune offer two different IDs:

• {{DeviceId}}: This ID is generated and used by Intune (Recommended). (Requires SCEPman 2.0 or higher and #AppConfig:IntuneValidation:DeviceDirectory to be set to Intune or AADAndIntune

• {{AAD_Device_ID}}: This ID is generated and used by Microsoft Entra ID (Azure AD).

You can add other RDNs if needed (e.g.: CN={{DeviceId}}, O=Contoso, CN={{WiFiMacAddress}}). Supported variables are listed in the Microsoft docs.

Subject alternative name: URI Value:IntuneDeviceId://{{DeviceId}}

The URI field is recommended by Microsoft for NAC solutions to identify the devices based on their Intune Device ID.

Other SAN values like DNS can be added if needed.

Certificate validity period: 1 years

The amount of time remaining before the certificate expires. Default is set at one year.

SCEPman caps the certificate validity to the configured maximum in setting AppConfig:ValidityPeriodDays, but otherwise uses the validity configured in the request.

Key usage: Digital signature and key encipherment

Please activate both cryptographic actions.

Key size (bits): 4096

SCEPman supports 4096 bits.

Root Certificate: Profile from previous step

Please select the Intune profile from [Root Certificate](android.md#root-certificate).

If you are using an Intermediate CA, you must still select the Trusted certificate profile for Root CA, not the Intermediate CA!

Extended key usage: Client Authentication, 1.3.6.1.5.5.7.3.2

Please choose Client Authentication (1.3.6.1.5.5.7.3.2) under Predefined values. The other fields will be filled out automatically.

Renewal threshold (%): 20

This value defines when the device is allowed to renew its certificate (based on the remaining lifetime of an existing certificate). Please read the note under Certificate validity period and select a suitable value that allows the device the renew the certificate over a long period. A value of 20% would allow the device with 1 year valid certificate to start renewal 73 days before expiration.

SCEP Server URLs: Open the SCEPman portal and copy the URL of #Intune MDM

Example

https://scepman.contoso.com/certsrv/mscep/mscep.dll

Example

User Certificates

Please follow the instructions of #Device certificates and take care of the following differences:

Certificate type: User

In this section we are setting up a user certificate.

Subject name format: CN={{UserName}},E={{EmailAddress}}

You can define RDNs based on your needs. Supported variables are listed in the Microsoft docs. We recommend to include the username (e.g.: janedoe) and email address (e.g.: [e-mail]) as baseline setting.

Subject alternative name: (UPN)Value: {{UserPrincipalName}}

You must add the User principal name as the Subject alternative name. Add '{{UserPrincipalName}}' as Subject Alternative Name of type User principal name (UPN). This ensures that SCEPman can link certificates to user objects in AAD.

Other SAN values like an Email address can be added if needed.

It is required to have a Subject alternative name in the SCEP Certificate, User Type. Without a SAN, you have no access to your company's Wi-Fi.

Example

Certificate Check

To ensure the correct deployment of certificates on your Android device, there are two options:

• In newer Android versions (e.g. 14), you can verify certificates (user and trusted certs.) from the settings > security and privacy

• Via 3rd party apps like X509 Certificate Viewer Tool