How do I renew expired SAML certificate?

Issue

We just noticed while browsing through the admin settings that apparently our SAML certificate expired four months ago, but our SSO and login works with no issue. We use Azure AD (Entra) for the Identity Provider and are now curious then what this certificate is for as well as any consequence for not renewing it?

SAML certificates are used for secure logins in order for different organizations to trust each other's user accounts. They are used to verify the integrity and authenticity of the data being exchanged between the different parties involved in a SAML login. Liferay uses the certificate to exchange signature, but not for peer validation which explains why your users are still able to authenticate with an expired certificate.
Simply click the 'Renew Certificate' button in the SAML admin settings as needed.
Or depending on your environment needs you can reference this third party article at your discretion to renew the certificate: https://learn.microsoft.com/en-us/entra/identity/enterprise-apps/tutorial-manage-certificates-for-federated-single-sign-on#renew-a-certificate-that-is-set-to-expire-soon