Duo SAML Implementation
This article contains Duo-specific help for configuring login with SSO via SAML 2.0 For help configuring login with SSO for another IdP, refer to SAML 2.0 Configuration.
Configuration involves working simultaneously between the Bitwarden web vault and the Duo Admin Portal. As you proceed, we recommend having both readily available and completing steps in the order they are documented.
Already an SSO expert? Skip the instructions in this article and download screenshots of sample configurations to compare against your own.
This article assumes that you have already set up Duo with an Identity Provider. If you haven't, see Duo's documentation for details.
Navigate to your organization's Settings → Single sign-on screen:
If you haven't already, create a unique SSO identifier for your organization. Otherwise, you don't need to edit anything on this screen yet, but keep it open for easy reference.
Before continuing, please refer to Duo's documentation to verify that Duo Single Sign-On has been configured with your SAML identity provider for authentication.
In the Duo Admin Portal, navigate to the Applications screen and select the Protect an Application button:
In the search bar, type
generic service provider and select Generic Service Provider (Single Sign-On):
Complete the following steps and configurations on the Application configuration screen, some of which you will need to retrieve from the Bitwarden Single Sign-On screen:
You don't need to edit anything in the Metadata section, but you will need to use these values later:
Select the Download certificate button to download your X.509 Certificate, as you will need to use it later in the configuration.
Set this field to the pre-generated SP Entity ID retrieved from the Bitwarden SSO configuration screen.
Assertion Consumer Service (ACS) URL
Set this field to the pre-generated Assertion Consumer Service (ACS) URL retrieved from the Bitwarden SSO Configuration screen.
Service Provider Login URL
Set this field to the login URL from which users will access Bitwarden.
Set this field to the SAML NameID format for Duo to send in SAML responses.
Set this field to the Duo attribute that will populate the NameID in responses.
Set this field to the encryption algorithm to use for SAML assertions and responses.
Select whether to Sign response, Sign assertion, or both.
Use these fields to map IdP attributes to SAML response attributes. Regardless of which NameID attribute you configured, map the IdP
Once you have finished configuring these fields, Save your changes.
At this point, you have configured everything you need within the context of the Duo Portal. return to the Bitwarden web vault to complete configuration.
The Single Sign-On screen separates configuration into two sections:
SAML Service Provider Configuration will determine the format of SAML requests.
SAML Identity Provider Configuration will determine the format to expect for SAML responses.
Configure the following fields according to the choices selected in the Duo Admin Portal during application setup:
Name ID Format
Outbound Signing Algorithm
Algorithm used to sign SAML requests, by default
Whether/when SAML requests will be signed. By default, Duo will not require requests to be signed.
Minimum Incoming Signing Algorithm
The minimum signing algorithm Bitwarden will accept in SAML responses. By default, Duo will sign with
Want Assertions Signed
Whether Bitwarden wants SAML assertions signed. Check this box if you selected the Sign assertion signing option.
Check this box when using trusted and valid certificates from your IdP through a trusted CA. Self-signed certificates may fail unless proper trust chains are configured within the Bitwarden Login with SSO docker image.
When you are done with the service provider configuration, Save your work.
Identity provider configuration will often require you to refer back to the Duo Admin Portal to retrieve application values:
Enter the Entity ID value of your Duo application, which can be retrieved from the Duo app Metadata section. This field is case sensitive.
Set this field to HTTP Post.
Single Sign On Service URL
Enter the Single Sign-On URL value of your Duo application, which can be retrieved from the Duo app Metadata section.
Single Log Out Service URL
Login with SSO currently does not support SLO. This option is planned for future development, however you may pre-configure with the Single Log-Out URL value of your Duo application.
X509 Public Certificate
Paste the downloaded certificate, removing
Outbound Signing Algorithm
Set this field to the selected SAML Response signature algorithm.
Disable Outbound Logout Requests
Login with SSO currently does not support SLO. This option is planned for future development.
Want Authentication Requests Signed
Whether Duo expects SAML requests to be signed.
When completing the X509 certificate, take note of the expiration date. Certificates will have to be renewed in order to prevent any disruptions in service to SSO end users. If a certificate has expired, Admin and Owner accounts will always be able to log in with email address and master password.
When you are done with the identity provider configuration, Save your work.
You can require users to log in with SSO by activating the single sign-on authentication policy. Please note, this will require activating the single organization policy as well. Learn more.
Once your configuration is complete, test it by navigating to https://vault.bitwarden.com, entering your email address, selecting Continue, and selecting the Enterprise Single-On button:
Enter the configured organization identifier and select Log In. If your implementation is successfully configured, you will be redirected to your source IdP's login screen.
After you authenticate with your IdP login and Duo Two-factor, enter your Bitwarden master password to decrypt your vault!
Bitwarden does not support unsolicited responses, so initiating login from your IdP will result in an error. The SSO login flow must be initiated from Bitwarden.