Fix #20232: Fix regression introduced in GHSA-cjcc-p67m-7qxm while attaching behavior defined by __class array key

Author: erickskrauch

framework/CHANGELOG.md

@@ -4,8 +4,7 @@ Yii Framework 2 Change Log
 2.0.52 under development
 ------------------------
 
-- no changes in this release.
-
+- Bug #20232: Fix regression introduced in `GHSA-cjcc-p67m-7qxm` while attaching behavior defined by `__class` array key (erickskrauch)
 
 2.0.51 July 18, 2024
 --------------------

framework/base/Component.php

@@ -190,7 +190,7 @@ public function __set($name, $value)
             $name = trim(substr($name, 3));
             if ($value instanceof Behavior) {
                 $this->attachBehavior($name, $value);
-            } elseif (isset($value['class']) && is_subclass_of($value['class'], Behavior::class, true)) {
+            } elseif ((isset($value['class']) && is_subclass_of($value['class'], Behavior::class)) || (isset($value['__class']) && is_subclass_of($value['__class'], Behavior::class))) {
                 $this->attachBehavior($name, Yii::createObject($value));
             } elseif (is_string($value) && is_subclass_of($value, Behavior::class, true)) {
                 $this->attachBehavior($name, Yii::createObject($value));

tests/framework/base/ComponentTest.php

@@ -341,6 +341,9 @@ public function testAttachBehavior()
         $this->assertTrue($component->hasProperty('p'));
         $component->test();
         $this->assertTrue($component->behaviorCalled);
+
+        $component->{'as c'} = ['__class' => NewBehavior::class];
+        $this->assertNotNull($component->getBehavior('c'));
     }
 
     public function testAttachBehaviors()