.../ckeditor/Plugin/CKEditorPlugin/Internal.php    |   20 ++++++++++++--------
 .../lib/Drupal/ckeditor/Tests/CKEditorTest.php     |    6 ++++--
 2 files changed, 16 insertions(+), 10 deletions(-)

diff --git a/core/modules/ckeditor/lib/Drupal/ckeditor/Plugin/CKEditorPlugin/Internal.php b/core/modules/ckeditor/lib/Drupal/ckeditor/Plugin/CKEditorPlugin/Internal.php
index d206597..5e8dec8 100644
--- a/core/modules/ckeditor/lib/Drupal/ckeditor/Plugin/CKEditorPlugin/Internal.php
+++ b/core/modules/ckeditor/lib/Drupal/ckeditor/Plugin/CKEditorPlugin/Internal.php
@@ -320,8 +320,12 @@ protected function generateAllowedContentSetting(Editor $editor) {
             'classes' => FALSE,
           );
         }
-        // Tell CKEditor the tag is allowed, as well as any attribute on it.
-        else if ($attributes === TRUE) {
+        // Tell CKEditor the tag is allowed, as well as any attribute on it. The
+        // "style" and "class" attributes are handled separately by CKEditor:
+        // they are disallowed even if you specify it in the list of allowed
+        // attributes, unless you state specific values for them that are
+        // allowed. Or, in this case: any value for them is allowed.
+        elseif ($attributes === TRUE) {
           $setting[$tag] = array(
             'attributes' => TRUE,
             'styles' => TRUE,
@@ -346,8 +350,8 @@ protected function generateAllowedContentSetting(Editor $editor) {
                 $setting[$tag]['styles'] = $wildcard['style'];
               }
               else {
-                $allowed_styles = $get_allowed_attribute_values($attributes['style']);
-                if (isset($allowed_values)) {
+                $allowed_styles = $get_allowed_attribute_values($wildcard['style']);
+                if (isset($allowed_styles)) {
                   $setting[$tag]['styles'] = $allowed_styles;
                 }
                 else {
@@ -360,9 +364,9 @@ protected function generateAllowedContentSetting(Editor $editor) {
                 $setting[$tag]['classes'] = $wildcard['class'];
               }
               else {
-                $allowed_styles = $get_allowed_attribute_values($attributes['class']);
-                if (isset($allowed_values)) {
-                  $setting[$tag]['classes'] = $allowed_styles;
+                $allowed_classes = $get_allowed_attribute_values($wildcard['class']);
+                if (isset($allowed_classes)) {
+                  $setting[$tag]['classes'] = $allowed_classes;
                 }
                 else {
                   unset($setting[$tag]['classes']);
@@ -372,7 +376,7 @@ protected function generateAllowedContentSetting(Editor $editor) {
           }
         }
         // Tell CKEditor the tag is allowed, along with some tags.
-        else if (is_array($attributes)) {
+        elseif (is_array($attributes)) {
           // CKEditor does not yet support blacklisting, so ignore those.
           // @todo Update this once http://dev.ckeditor.com/ticket/10276 lands.
           $attributes = array_filter($attributes, function($value) {
diff --git a/core/modules/ckeditor/lib/Drupal/ckeditor/Tests/CKEditorTest.php b/core/modules/ckeditor/lib/Drupal/ckeditor/Tests/CKEditorTest.php
index 9655051..15228d2 100644
--- a/core/modules/ckeditor/lib/Drupal/ckeditor/Tests/CKEditorTest.php
+++ b/core/modules/ckeditor/lib/Drupal/ckeditor/Tests/CKEditorTest.php
@@ -147,6 +147,7 @@ function testGetJSSettings() {
             ),
             '*' => array(
               'style' => FALSE,
+              'class' => array('is-a-hipster-llama' => TRUE, 'and-more' => TRUE),
               'data-*' => TRUE,
             ),
             'del' => FALSE,
@@ -159,7 +160,7 @@ function testGetJSSettings() {
       'p' => array(
         'attributes' => TRUE,
         'styles' => FALSE,
-        'classes' => TRUE,
+        'classes' => 'is-a-hipster-llama,and-more',
       ),
       'a' => array(
         'attributes' => 'href,rel,class,target',
@@ -169,7 +170,8 @@ function testGetJSSettings() {
         'attributes' => 'class,property,rel',
       ),
       '*' => array(
-        'attributes' => 'data-*',
+        'attributes' => 'class,data-*',
+        'classes' => 'is-a-hipster-llama,and-more',
       ),
       'del' => array(
         'attributes' => FALSE,