diff --git a/mod/quiz/classes/external.php b/mod/quiz/classes/external.php
index 4cc7a7aa7a9..5c3b4098756 100644
--- a/mod/quiz/classes/external.php
+++ b/mod/quiz/classes/external.php
@@ -968,41 +968,18 @@ class mod_quiz_external extends external_api {
             $qattempt = $attemptobj->get_question_attempt($slot);
             $questiondef = $qattempt->get_question(true);
 
-            // Get response files (for questions like essay that allows attachments).
-            $responsefileareas = [];
-            foreach (question_bank::get_qtype($qtype)->response_file_areas() as $area) {
-                if ($files = $attemptobj->get_question_attempt($slot)->get_last_qt_files($area, $contextid)) {
-                    $responsefileareas[$area]['area'] = $area;
-                    $responsefileareas[$area]['files'] = [];
-
-                    foreach ($files as $file) {
-                        $responsefileareas[$area]['files'][] = [
-                            'filename' => $file->get_filename(),
-                            'fileurl' => $qattempt->get_response_file_url($file),
-                            'filesize' => $file->get_filesize(),
-                            'filepath' => $file->get_filepath(),
-                            'mimetype' => $file->get_mimetype(),
-                            'timemodified' => $file->get_timemodified(),
-                        ];
-                    }
-                }
-            }
-
             // Check display settings for question.
             $settings = $questiondef->get_question_definition_for_external_rendering($qattempt, $displayoptions);
 
+            // Navigation information.
             $question = [
                 'slot' => $slot,
-                'type' => $qtype,
                 'page' => $attemptobj->get_question_page($slot),
                 'questionnumber' => $attemptobj->get_question_number($slot),
                 'flagged' => $attemptobj->is_question_flagged($slot),
-                'html' => $attemptobj->render_question($slot, $review, $renderer) . $PAGE->requires->get_end_code(),
-                'responsefileareas' => $responsefileareas,
                 'sequencecheck' => $qattempt->get_sequence_check_count(),
                 'lastactiontime' => $qattempt->get_last_step()->get_timecreated(),
                 'hasautosavedstep' => $qattempt->has_autosaved_step(),
-                'settings' => !empty($settings) ? json_encode($settings) : null,
             ];
 
             if ($question['questionnumber'] === (string) (int) $question['questionnumber']) {
@@ -1023,9 +1000,44 @@ class mod_quiz_external extends external_api {
             if ($displayoptions->marks >= question_display_options::MARK_AND_MAX) {
                 $question['mark'] = $attemptobj->get_question_mark($slot);
             }
-            if ($attemptobj->check_page_access($attemptobj->get_question_page($slot), false)) {
-                $questions[] = $question;
+
+            // Check access. This is needed especially when sequential navigation is enforced. To prevent the student see "future" questions.
+            $haveaccess = $attemptobj->check_page_access($attemptobj->get_question_page($slot), false);
+            if (!$haveaccess) {
+                $question['type'] = '';
+                $question['html'] = '';
             }
+
+            // For visited pages/questions it is ok to keep data the user already saw.
+            $questionalreadyseen = $attemptobj->get_currentpage() >= $attemptobj->get_question_page($slot);
+
+            // Information when only the user has access to the question at any moment (free navigation) or already seen.
+            if ($haveaccess || $questionalreadyseen) {
+                // Get response files (for questions like essay that allows attachments).
+                $responsefileareas = [];
+                foreach (question_bank::get_qtype($qtype)->response_file_areas() as $area) {
+                    if ($files = $attemptobj->get_question_attempt($slot)->get_last_qt_files($area, $contextid)) {
+                        $responsefileareas[$area]['area'] = $area;
+                        $responsefileareas[$area]['files'] = [];
+
+                        foreach ($files as $file) {
+                            $responsefileareas[$area]['files'][] = [
+                                'filename' => $file->get_filename(),
+                                'fileurl' => $qattempt->get_response_file_url($file),
+                                'filesize' => $file->get_filesize(),
+                                'filepath' => $file->get_filepath(),
+                                'mimetype' => $file->get_mimetype(),
+                                'timemodified' => $file->get_timemodified(),
+                            ];
+                        }
+                    }
+                }
+                $question['type'] = $qtype;
+                $question['html'] = $attemptobj->render_question($slot, $review, $renderer) . $PAGE->requires->get_end_code();
+                $question['responsefileareas'] = $responsefileareas;
+                $question['settings'] = !empty($settings) ? json_encode($settings) : null;
+            }
+            $questions[] = $question;
         }
         return $questions;
     }
diff --git a/mod/quiz/tests/external/external_test.php b/mod/quiz/tests/external/external_test.php
index d3796d5fbf7..5718aec9c85 100644
--- a/mod/quiz/tests/external/external_test.php
+++ b/mod/quiz/tests/external/external_test.php
@@ -2074,17 +2074,20 @@ class external_test extends externallib_advanced_testcase {
     }
 
     /**
-     * Test that a sequential navigation quiz is not allowing to see questions in advance for a student
+     * Test that a sequential navigation quiz is not allowing to see questions content in advance for a student.
      */
     public function test_sequential_navigation_attempt_summary() {
         // Test user with full capabilities.
         $quiz = $this->prepare_sequential_quiz();
         $attemptobj = $this->create_quiz_attempt_object($quiz);
         $this->setUser($this->student);
-        // Check that we do not return other questions than the one currently viewed.
+        // Check that we do not return content from other questions except than the ones currently viewed.
         $result = mod_quiz_external::get_attempt_summary($attemptobj->get_attemptid());
-        $this->assertCount(1, $result['questions']);
-        $this->assertStringContainsString('Question (1)', $result['questions'][0]['html']);
+        $this->assertStringContainsString('Question (1)', $result['questions'][0]['html']); // Current question.
+        $this->assertEmpty($result['questions'][1]['html']); // Next question.
+        $this->assertEmpty($result['questions'][2]['html']); // And more.
+        $this->assertEmpty($result['questions'][3]['html']); // And more.
+        $this->assertEmpty($result['questions'][4]['html']); // And more.
     }
 
     /**
@@ -2137,6 +2140,7 @@ class external_test extends externallib_advanced_testcase {
         $data = [
             'course' => $this->course->id,
             'sumgrades' => 2,
+            'questionsperpage' => 1,
             'preferredbehaviour' => 'deferredfeedback',
             'navmethod' => QUIZ_NAVMETHOD_SEQ
         ];