diff --git a/src/Symfony/Component/Yaml/Inline.php b/src/Symfony/Component/Yaml/Inline.php
index 1b34edebd2..fc00405a8b 100644
--- a/src/Symfony/Component/Yaml/Inline.php
+++ b/src/Symfony/Component/Yaml/Inline.php
@@ -392,7 +392,7 @@ class Inline
      *
      * @return string A YAML string
      *
-     * @throws ParseException when object parsing support was disabled and the parser detected a PHP object
+     * @throws ParseException when object parsing support was disabled and the parser detected a PHP object or when a reference could not be resolved
      */
     private static function evaluateScalar($scalar, $references = array())
     {
@@ -406,6 +406,11 @@ class Inline
                 $value = substr($scalar, 1);
             }
 
+            // an unquoted *
+            if (false === $value || '' === $value) {
+                throw new ParseException('A reference must contain at least one character.');
+            }
+
             if (!array_key_exists($value, $references)) {
                 throw new ParseException(sprintf('Reference "%s" does not exist.', $value));
             }
diff --git a/src/Symfony/Component/Yaml/Tests/InlineTest.php b/src/Symfony/Component/Yaml/Tests/InlineTest.php
index 96a118d073..6b5da8df39 100644
--- a/src/Symfony/Component/Yaml/Tests/InlineTest.php
+++ b/src/Symfony/Component/Yaml/Tests/InlineTest.php
@@ -147,6 +147,24 @@ class InlineTest extends \PHPUnit_Framework_TestCase
         $this->assertSame(array($foo), Inline::parse('[*foo]', false, false, array('foo' => $foo)));
     }
 
+    /**
+     * @expectedException \Symfony\Component\Yaml\Exception\ParseException
+     * @expectedExceptionMessage A reference must contain at least one character.
+     */
+    public function testParseUnquotedAsterisk()
+    {
+        Inline::parse('{ foo: * }');
+    }
+
+    /**
+     * @expectedException \Symfony\Component\Yaml\Exception\ParseException
+     * @expectedExceptionMessage A reference must contain at least one character.
+     */
+    public function testParseUnquotedAsteriskFollowedByAComment()
+    {
+        Inline::parse('{ foo: * #foo }');
+    }
+
     protected function getTestsForParse()
     {
         return array(