diff --git a/phpBB/language/en/common.php b/phpBB/language/en/common.php
index 2fc7eeb12a..7443f27be3 100644
--- a/phpBB/language/en/common.php
+++ b/phpBB/language/en/common.php
@@ -95,6 +95,7 @@ $lang = array_merge($lang, array(
 	'AUTH_PROVIDER_OAUTH_ERROR_INVALID_ENTRY'				=> 'Invalid database entry.',
 	'AUTH_PROVIDER_OAUTH_ERROR_INVALID_SERVICE_TYPE'		=> 'Invalid service type provided to OAuth service handler.',
 	'AUTH_PROVIDER_OAUTH_ERROR_REQUEST'						=> 'Something went wrong when processing your OAuth request.',
+	'AUTH_PROVIDER_OAUTH_RETURN_ERROR'						=> 'The external service returned a wrong value therefore your request can not be processed.',
 	'AUTH_PROVIDER_OAUTH_ERROR_SERVICE_NOT_CREATED'			=> 'OAuth service not created',
 	'AUTH_PROVIDER_OAUTH_SERVICE_BITLY'						=> 'Bitly',
 	'AUTH_PROVIDER_OAUTH_SERVICE_FACEBOOK'					=> 'Facebook',
diff --git a/phpBB/phpbb/auth/provider/oauth/service/bitly.php b/phpBB/phpbb/auth/provider/oauth/service/bitly.php
index ca131b2019..0169de098e 100644
--- a/phpBB/phpbb/auth/provider/oauth/service/bitly.php
+++ b/phpBB/phpbb/auth/provider/oauth/service/bitly.php
@@ -77,6 +77,12 @@ class bitly extends base
 			throw new exception('AUTH_PROVIDER_OAUTH_ERROR_REQUEST');
 		}
 
+		// Prevent SQL error
+		if (!isset($result['data']['login']))
+		{
+			throw new exception('AUTH_PROVIDER_OAUTH_RETURN_ERROR');
+		}
+
 		// Return the unique identifier returned from bitly
 		return $result['data']['login'];
 	}
@@ -101,6 +107,12 @@ class bitly extends base
 			throw new exception('AUTH_PROVIDER_OAUTH_ERROR_REQUEST');
 		}
 
+		// Prevent SQL error
+		if (!isset($result['data']['login']))
+		{
+			throw new exception('AUTH_PROVIDER_OAUTH_RETURN_ERROR');
+		}
+
 		// Return the unique identifier
 		return $result['data']['login'];
 	}