diff --git a/lib/endpoints/class-wp-rest-comments-controller.php b/lib/endpoints/class-wp-rest-comments-controller.php
index 4c7f671967..3605d2acef 100644
--- a/lib/endpoints/class-wp-rest-comments-controller.php
+++ b/lib/endpoints/class-wp-rest-comments-controller.php
@@ -158,6 +158,21 @@ public function create_item( $request ) {
 		if ( ! isset( $prepared_comment['comment_date_gmt'] ) ) {
 			$prepared_comment['comment_date_gmt'] = current_time( 'mysql', true );
 		}
+
+		// Set author data if the user's logged in
+		$missing_author = empty( $prepared_comment['user_id'] )
+			&& empty( $prepared_comment['comment_author'] )
+			&& empty( $prepared_comment['comment_author_email'] )
+			&& empty( $prepared_comment['comment_author_url'] );
+
+		if ( is_user_logged_in() && $missing_author ) {
+			$user = wp_get_current_user();
+			$prepared_comment['user_id'] = $user->ID;
+			$prepared_comment['comment_author'] = $user->display_name;
+			$prepared_comment['comment_author_email'] = $user->user_email;
+			$prepared_comment['comment_author_url'] = $user->user_url;
+		}
+
 		if ( ! isset( $prepared_comment['comment_author_email'] ) ) {
 			$prepared_comment['comment_author_email'] = '';
 		}
diff --git a/tests/test-rest-comments-controller.php b/tests/test-rest-comments-controller.php
index 1b632d1086..133c42c2ae 100644
--- a/tests/test-rest-comments-controller.php
+++ b/tests/test-rest-comments-controller.php
@@ -386,6 +386,32 @@ public function test_create_item_assign_different_user() {
 		$this->assertEquals( $this->subscriber_id, $data['author'] );
 	}
 
+	public function test_create_item_current_user() {
+		wp_set_current_user( $this->subscriber_id );
+
+		$params = array(
+			'post' => $this->post_id,
+			'content' => "Well sir, there's nothing on earth like a genuine, bona fide, electrified, six-car Monorail!",
+		);
+
+		$request = new WP_REST_Request( 'POST', '/wp/v2/comments' );
+		$request->add_header( 'content-type', 'application/json' );
+		$request->set_body( wp_json_encode( $params ) );
+		$response = $this->server->dispatch( $request );
+
+		$response = rest_ensure_response( $response );
+		$this->assertEquals( 201, $response->get_status() );
+		$data = $response->get_data();
+		$this->assertEquals( $this->subscriber_id, $data['author'] );
+
+		// Check author data matches
+		$author = get_user_by( 'id', $this->subscriber_id );
+		$comment = get_comment( $data['id'] );
+		$this->assertEquals( $author->display_name, $comment->comment_author );
+		$this->assertEquals( $author->user_email, $comment->comment_author_email );
+		$this->assertEquals( $author->user_url, $comment->comment_author_url );
+	}
+
 	public function test_create_comment_other_user() {
 		wp_set_current_user( $this->admin_id );