diff --git a/app/Controller/CurrencyController.php b/app/Controller/CurrencyController.php
index 513dd98..58fa8b4 100644
--- a/app/Controller/CurrencyController.php
+++ b/app/Controller/CurrencyController.php
@@ -91,7 +91,7 @@ class CurrencyController extends BaseController
      */
     public function update()
     {
-        $values = $this->request->getValues();
+        $values = array_intersect_key($this->request->getValues(), array('application_currency' => ''));
 
         if ($this->configModel->save($values)) {
             $this->flash->success(t('Settings saved successfully.'));
diff --git a/app/Controller/ICalendarController.php b/app/Controller/ICalendarController.php
index fbbd63a..dd3ae46 100644
--- a/app/Controller/ICalendarController.php
+++ b/app/Controller/ICalendarController.php
@@ -31,7 +31,7 @@ class ICalendarController extends BaseController
         $startRange = strtotime('-2 months');
         $endRange = strtotime('+6 months');
 
-        $startColumn = $this->configModel->get('calendar_user_tasks', 'date_started');
+        $startColumn = $this->getStartColumn('calendar_user_tasks');
 
         $calendar = new iCalendar('Kanboard');
         $calendar->setName($user['name'] ?: $user['username']);
@@ -71,7 +71,7 @@ class ICalendarController extends BaseController
         $startRange = strtotime('-2 months');
         $endRange = strtotime('+6 months');
 
-        $startColumn = $this->configModel->get('calendar_project_tasks', 'date_started');
+        $startColumn = $this->getStartColumn('calendar_project_tasks');
 
         $calendar = new iCalendar('Kanboard');
         $calendar->setName($project['name']);
@@ -99,6 +99,12 @@ class ICalendarController extends BaseController
             ->format());
     }
 
+    protected function getStartColumn($option)
+    {
+        $column = $this->configModel->get($option, 'date_started');
+        return in_array($column, array('date_creation', 'date_started'), true) ? $column : 'date_started';
+    }
+
     protected function getConditionForTasksWithStartAndDueDate($start_time, $end_time, $start_column, $end_column)
     {
         $start_time = (int) $start_time;
diff --git a/tests/units/Controller/CurrencyControllerTest.php b/tests/units/Controller/CurrencyControllerTest.php
new file mode 100644
index 0000000..98a1a0e
--- /dev/null
+++ b/tests/units/Controller/CurrencyControllerTest.php
@@ -0,0 +1,41 @@
+<?php
+
+namespace KanboardTests\units\Controller;
+
+use Kanboard\Controller\CurrencyController;
+use Kanboard\Core\Http\Request;
+use Kanboard\Core\Http\Response;
+use KanboardTests\units\Base;
+
+class CurrencyControllerTest extends Base
+{
+    public function testChangingTheCurrencyDoesNotSaveOtherSettings()
+    {
+        $this->container['request'] = new Request(
+            $this->container,
+            array('REQUEST_METHOD' => 'POST'),
+            array(),
+            array(
+                'csrf_token' => $this->container['token']->getCSRFToken(),
+                'application_currency' => 'EUR',
+                'calendar_project_tasks' => '1 OR 1=1 OR 1',
+            ),
+            array(),
+            array()
+        );
+
+        $this->container['response'] = $this->getMockBuilder(Response::class)
+            ->setConstructorArgs(array($this->container))
+            ->onlyMethods(array('redirect'))
+            ->getMock();
+
+        $this->container['response']
+            ->expects($this->once())
+            ->method('redirect');
+
+        (new CurrencyController($this->container))->update();
+
+        $this->assertEquals('EUR', $this->container['configModel']->getOption('application_currency'));
+        $this->assertEquals('date_started', $this->container['configModel']->getOption('calendar_project_tasks'));
+    }
+}
diff --git a/tests/units/Controller/ICalendarControllerTest.php b/tests/units/Controller/ICalendarControllerTest.php
new file mode 100644
index 0000000..8fc5496
--- /dev/null
+++ b/tests/units/Controller/ICalendarControllerTest.php
@@ -0,0 +1,92 @@
+<?php
+
+namespace KanboardTests\units\Controller;
+
+use Kanboard\Controller\ICalendarController;
+use Kanboard\Core\Http\Request;
+use Kanboard\Core\Http\Response;
+use KanboardTests\units\Base;
+
+class ICalendarControllerTest extends Base
+{
+    private $calendar = '';
+
+    public function testProjectCalendarIgnoresUnknownStartColumn()
+    {
+        $this->container['configModel']->save(array('calendar_project_tasks' => '1 OR 1=1 OR 1'));
+        $this->createFixtures();
+        $project = $this->container['projectModel']->getById(1);
+
+        $this->renderCalendar(array('token' => $project['token']))->project();
+
+        $this->assertStringNotContainsString('Private task', $this->calendar);
+        $this->assertStringContainsString('Public task', $this->calendar);
+        $this->assertStringContainsString('task-#1-date_started-date_due', $this->calendar);
+    }
+
+    public function testUserCalendarIgnoresUnknownStartColumn()
+    {
+        $this->container['configModel']->save(array('calendar_user_tasks' => '1 OR 1=1 OR 1'));
+        $this->createFixtures();
+        $user = $this->container['userModel']->getById(2);
+
+        $this->renderCalendar(array('token' => $user['token']))->user();
+
+        $this->assertStringNotContainsString('Private task', $this->calendar);
+        $this->assertStringContainsString('Public task', $this->calendar);
+    }
+
+    public function testProjectCalendarUsesCreationDateWhenConfigured()
+    {
+        $this->container['configModel']->save(array('calendar_project_tasks' => 'date_creation'));
+        $this->createFixtures();
+        $project = $this->container['projectModel']->getById(1);
+
+        $this->renderCalendar(array('token' => $project['token']))->project();
+
+        $this->assertStringContainsString('task-#1-date_creation-date_due', $this->calendar);
+    }
+
+    private function createFixtures()
+    {
+        $this->assertEquals(2, $this->container['userModel']->create(array('username' => 'user1')));
+        $this->assertTrue($this->container['userModel']->enablePublicAccess(2));
+
+        $this->assertEquals(1, $this->container['projectModel']->create(array('name' => 'Public project')));
+        $this->assertTrue($this->container['projectModel']->enablePublicAccess(1));
+        $this->assertEquals(2, $this->container['projectModel']->create(array('name' => 'Private project')));
+
+        $this->assertEquals(1, $this->createTask(1, 'Public task', 2));
+        $this->assertEquals(2, $this->createTask(2, 'Private task', 1));
+    }
+
+    private function createTask($projectId, $title, $ownerId)
+    {
+        return $this->container['taskCreationModel']->create(array(
+            'project_id' => $projectId,
+            'title' => $title,
+            'owner_id' => $ownerId,
+            'date_started' => strtotime('-1 day'),
+            'date_due' => strtotime('+1 day'),
+        ));
+    }
+
+    private function renderCalendar(array $params)
+    {
+        $this->container['request'] = new Request($this->container, array('REQUEST_METHOD' => 'GET'), $params);
+
+        $this->container['response'] = $this->getMockBuilder(Response::class)
+            ->setConstructorArgs(array($this->container))
+            ->onlyMethods(array('ical'))
+            ->getMock();
+
+        $this->container['response']
+            ->expects($this->once())
+            ->method('ical')
+            ->willReturnCallback(function ($calendar) {
+                $this->calendar = $calendar;
+            });
+
+        return new ICalendarController($this->container);
+    }
+}