diff --git a/app/Auth/Access/ExternalAuthService.php b/app/Auth/Access/ExternalAuthService.php
index db8bd2dfb..7f15307ae 100644
--- a/app/Auth/Access/ExternalAuthService.php
+++ b/app/Auth/Access/ExternalAuthService.php
@@ -3,9 +3,46 @@
 use BookStack\Auth\Role;
 use BookStack\Auth\User;
 use Illuminate\Database\Eloquent\Builder;
+use Illuminate\Support\Str;
 
 class ExternalAuthService
 {
+    protected $registrationService;
+    protected $user;
+
+    /**
+     * ExternalAuthService base constructor.
+     */
+    public function __construct(RegistrationService $registrationService, User $user)
+    {
+        $this->registrationService = $registrationService;
+        $this->user = $user;
+    }
+    
+    /**
+     * Get the user from the database for the specified details.
+     * @throws UserRegistrationException
+     */
+    protected function getOrRegisterUser(array $userDetails): ?User
+    {
+        $user = $this->user->newQuery()
+          ->where('external_auth_id', '=', $userDetails['external_id'])
+          ->first();
+
+        if (is_null($user)) {
+            $userData = [
+                'name' => $userDetails['name'],
+                'email' => $userDetails['email'],
+                'password' => Str::random(32),
+                'external_auth_id' => $userDetails['external_id'],
+            ];
+
+            $user = $this->registrationService->registerUser($userData, null, false);
+        }
+
+        return $user;
+    }
+
     /**
      * Check a role against an array of group names to see if it matches.
      * Checked against role 'external_auth_id' if set otherwise the name of the role.
diff --git a/app/Auth/Access/OpenIdService.php b/app/Auth/Access/OpenIdService.php
index 870299a57..084adfb13 100644
--- a/app/Auth/Access/OpenIdService.php
+++ b/app/Auth/Access/OpenIdService.php
@@ -5,7 +5,6 @@ use BookStack\Exceptions\JsonDebugException;
 use BookStack\Exceptions\OpenIdException;
 use BookStack\Exceptions\UserRegistrationException;
 use Exception;
-use Illuminate\Support\Str;
 use Lcobucci\JWT\Token;
 use OpenIDConnectClient\AccessToken;
 use OpenIDConnectClient\OpenIDConnectProvider;
@@ -17,17 +16,15 @@ use OpenIDConnectClient\OpenIDConnectProvider;
 class OpenIdService extends ExternalAuthService
 {
     protected $config;
-    protected $registrationService;
-    protected $user;
 
     /**
      * OpenIdService constructor.
      */
     public function __construct(RegistrationService $registrationService, User $user)
     {
+        parent::__construct($registrationService, $user);
+        
         $this->config = config('openid');
-        $this->registrationService = $registrationService;
-        $this->user = $user;
     }
 
     /**
@@ -175,31 +172,6 @@ class OpenIdService extends ExternalAuthService
         ];
     }
 
-    /**
-     * Get the user from the database for the specified details.
-     * @throws OpenIdException
-     * @throws UserRegistrationException
-     */
-    protected function getOrRegisterUser(array $userDetails): ?User
-    {
-        $user = $this->user->newQuery()
-          ->where('external_auth_id', '=', $userDetails['external_id'])
-          ->first();
-
-        if (is_null($user)) {
-            $userData = [
-                'name' => $userDetails['name'],
-                'email' => $userDetails['email'],
-                'password' => Str::random(32),
-                'external_auth_id' => $userDetails['external_id'],
-            ];
-
-            $user = $this->registrationService->registerUser($userData, null, false);
-        }
-
-        return $user;
-    }
-
     /**
      * Processes a received access token for a user. Login the user when
      * they exist, optionally registering them automatically.
diff --git a/app/Auth/Access/Saml2Service.php b/app/Auth/Access/Saml2Service.php
index 8f9a24cde..4c1fce864 100644
--- a/app/Auth/Access/Saml2Service.php
+++ b/app/Auth/Access/Saml2Service.php
@@ -5,7 +5,6 @@ use BookStack\Exceptions\JsonDebugException;
 use BookStack\Exceptions\SamlException;
 use BookStack\Exceptions\UserRegistrationException;
 use Exception;
-use Illuminate\Support\Str;
 use OneLogin\Saml2\Auth;
 use OneLogin\Saml2\Error;
 use OneLogin\Saml2\IdPMetadataParser;
@@ -18,17 +17,15 @@ use OneLogin\Saml2\ValidationError;
 class Saml2Service extends ExternalAuthService
 {
     protected $config;
-    protected $registrationService;
-    protected $user;
 
     /**
      * Saml2Service constructor.
      */
     public function __construct(RegistrationService $registrationService, User $user)
     {
+        parent::__construct($registrationService, $user);
+        
         $this->config = config('saml2');
-        $this->registrationService = $registrationService;
-        $this->user = $user;
     }
 
     /**
@@ -309,31 +306,6 @@ class Saml2Service extends ExternalAuthService
         return $defaultValue;
     }
 
-    /**
-     * Get the user from the database for the specified details.
-     * @throws SamlException
-     * @throws UserRegistrationException
-     */
-    protected function getOrRegisterUser(array $userDetails): ?User
-    {
-        $user = $this->user->newQuery()
-          ->where('external_auth_id', '=', $userDetails['external_id'])
-          ->first();
-
-        if (is_null($user)) {
-            $userData = [
-                'name' => $userDetails['name'],
-                'email' => $userDetails['email'],
-                'password' => Str::random(32),
-                'external_auth_id' => $userDetails['external_id'],
-            ];
-
-            $user = $this->registrationService->registerUser($userData, null, false);
-        }
-
-        return $user;
-    }
-
     /**
      * Process the SAML response for a user. Login the user when
      * they exist, optionally registering them automatically.