WordPress Strong Authentication lets you authenticate users with a second
factor of possession.
Only if the user is able to provide this second factor, he is allowed to login.
Such a second factor can be an OTP display card, an OTP hardware token, a Yubikey,
a smartphone App like the Google Authenticator or access to an mobile phone
to receive an SMS or access to an email account.
The use then needs to authenticate with his wordpress password and in addition with
a code, generated by his device or sent via email or SMS.
All the devices are managed in the backend (privacyIDEA)[http://privacyidea.org], the Strong Authentication
plugin forwards authentication requests to this backend, which you can easily run
on the same machine or anywhere in your network.
Please add at least a hostname or IP address of your backend server privacyIDEA.
You need to enter the hostname together with the protocol and the port, if it is
not a standard port.
If you are using self signed certificates, you should disable the verification of hostname and peer.
Please note: You need to have the same users in the LinOTP server.
You can achieve this by configuring an SQL Resolver and presetting this to
If you misconfigured the plugin, you might not be able to authenticate anymore!
So it is always a good idea to add some users to the “excluded users” list.
These users will be able to authenticate without a second factor and
even if the authentication server should be down.
Another possibility is to disable the plugin by removing or renaming the
In this case is will fall back to the old wordpress passwords.
You can install this plugin from within your wordpress plugin menu.
Alternatively you can install it manually:
For installing the wordpress plugin simply copy the file
wp-strong-authentication.php to the wordpress directory
Q: What happens if my authentication backend is offline?
A: If your authentication backend is offline, the users are not able
to authenticate with OTP. This is the same as if you SQL server is down
or your LDAP server is not reachable.
Alas, you can configure certain users, who will not be authenticated against
the backend but within wordpres. This can be an emergency entry.
Contributors & Developers
“WordPress Strong Authentication” is open source software. The following people have contributed to this plugin.
Interested in development?
- Add user-agent to POST request
- Fixed and error in displaying errors :-/
- remove php curl and use WP HTTP class instead
- Add possibility to exclude users from two factor authentication