diff --git a/src/Libraries/GithubOAuth.php b/src/Libraries/GithubOAuth.php
index f317be7..4342e37 100644
--- a/src/Libraries/GithubOAuth.php
+++ b/src/Libraries/GithubOAuth.php
@@ -21,10 +21,12 @@
 
 class GithubOAuth extends AbstractOAuth
 {
-    public static string $API_CODE_URL      = 'https://github.com/login/oauth/authorize';
-    public static string $API_TOKEN_URL     = 'https://github.com/login/oauth/access_token';
-    public static string $API_USER_INFO_URL = 'https://api.github.com/user';
-    private static string $APPLICATION_NAME = 'ShieldOAuth';
+    public static string $API_CODE_URL        = 'https://github.com/login/oauth/authorize';
+    public static string $API_TOKEN_URL       = 'https://github.com/login/oauth/access_token';
+    public static string $API_USER_INFO_URL   = 'https://api.github.com/user';         // The /user API returns the user's publicly visible data or null for those that are not set
+    public static string $API_USER_EMAILS_URL = 'https://api.github.com/user/emails';  // The /user/emails API returns all email addresses for the user, including those that are not set public
+    private static string $APPLICATION_NAME   = 'ShieldOAuth';
+
     protected string $token;
     protected CURLRequest $client;
     protected ShieldOAuthConfig $config;
@@ -89,7 +91,49 @@ protected function fetchUserInfoWithToken(): object
             exit($e->getMessage());
         }
 
-        return json_decode($response->getBody());
+        $userInfo = json_decode($response->getBody(), false);
+
+        // the email address is mandatory
+        if (empty($userInfo->email)) {
+            $userInfo->email = $this->getUserPrimaryEmail($this->fetchUserEmailsWithToken());
+        }
+
+        return $userInfo;
+    }
+
+    /**
+     * @return list<object>
+     */
+    protected function fetchUserEmailsWithToken(): array
+    {
+        // send request to API URL
+        try {
+            $response = $this->client->request('GET', self::$API_USER_EMAILS_URL, [
+                'headers' => [
+                    'User-Agent'    => self::$APPLICATION_NAME . '/1.0',
+                    'Accept'        => 'application/vnd.github+json',
+                    'Authorization' => 'Bearer ' . $this->getToken(),
+                ],
+                'http_errors' => false,
+            ]);
+        } catch (Exception $e) {
+            exit($e->getMessage());
+        }
+
+        return json_decode($response->getBody(), false);
+    }
+
+    /**
+     * @param list<object> $emailAddresses
+     */
+    protected function getUserPrimaryEmail(array $emailAddresses): string
+    {
+        // try to get the one marked as primary, otherwise grab the first one
+        if (! empty($emailAddresses)) {
+            $primaryEmail = array_filter($emailAddresses, static fn ($eMail) => $eMail->primary);
+            $userEmail    = ! empty($primaryEmail) ? array_shift($primaryEmail)->email : array_shift($emailAddresses)->email;
+        }
+        return $userEmail ?? '';
     }
 
     protected function setColumnsName(string $nameOfProcess, $userInfo): array