diff --git a/boards/templates/boards/thread_normal.html b/boards/templates/boards/thread_normal.html
--- a/boards/templates/boards/thread_normal.html
+++ b/boards/templates/boards/thread_normal.html
@@ -12,6 +12,7 @@
     <div class="tag_info">
         <h2>
             <form action="{% url 'thread' opening_post.id %}" method="post" class="post-button-form">
+                {% csrf_token %}
                 {% if is_favorite %}
                     <button name="method" value="unsubscribe" class="fav">★</button>
                 {% else %}