diff --git a/framework/CHANGELOG.md b/framework/CHANGELOG.md
index 2f88a822c9..991753c92a 100644
--- a/framework/CHANGELOG.md
+++ b/framework/CHANGELOG.md
@@ -4,6 +4,7 @@ Yii Framework 2 Change Log
 2.0.0 under development
 -----------------------
 
+- Bug #5252: Null values are not properly handled by `RangeValidator` (githubjeka, qiangxue)
 - Bug #5260: `yii\i18n\Formatter::decimalSeparator` and `yii\i18n\Formatter::thousandSeparator` where not configurable when intl is not installed (execut, cebe)
 - Bug #5314: Fixed typo in the implementation of `yii\web\Session::getHasSessionId()` (qiangxue)
 - Bug: Date and time formatting now assumes UTC as the timezone for input dates unless a timezone is explicitly given (cebe)
diff --git a/framework/validators/RangeValidator.php b/framework/validators/RangeValidator.php
index d58a8b8aaa..6ce9b2976e 100644
--- a/framework/validators/RangeValidator.php
+++ b/framework/validators/RangeValidator.php
@@ -66,7 +66,7 @@ class RangeValidator extends Validator
 
         $in = true;
 
-        foreach ((array)$value as $v) {
+        foreach ((is_array($value) ? $value : [$value]) as $v) {
             if (!in_array($v, $this->range, $this->strict)) {
                 $in = false;
                 break;
diff --git a/tests/unit/framework/validators/RangeValidatorTest.php b/tests/unit/framework/validators/RangeValidatorTest.php
index 5232b337f7..b4cbf32214 100644
--- a/tests/unit/framework/validators/RangeValidatorTest.php
+++ b/tests/unit/framework/validators/RangeValidatorTest.php
@@ -41,6 +41,17 @@ class RangeValidatorTest extends TestCase
         $this->assertTrue($val->validate("5"));
     }
 
+    public function testValidateValueEmpty()
+    {
+        $val = new RangeValidator(['range' => range(10, 20, 1), 'skipOnEmpty' => false]);
+        $this->assertFalse($val->validate(null)); //row RangeValidatorTest.php:101
+        $this->assertFalse($val->validate('0'));
+        $this->assertFalse($val->validate(0));
+        $this->assertFalse($val->validate(''));
+        $val->allowArray = true;
+        $this->assertTrue($val->validate([]));
+    }
+
     public function testValidateArrayValue()
     {
         $val = new RangeValidator(['range' => range(1, 10, 1)]);