diff --git a/puppet/services/horizon.yaml b/puppet/services/horizon.yaml
index e59dc202ed..d7f1075720 100644
--- a/puppet/services/horizon.yaml
+++ b/puppet/services/horizon.yaml
@@ -61,6 +61,7 @@ outputs:
           horizon::enable_secure_proxy_ssl_header: true
           horizon::disable_password_reveal: true
           horizon::enforce_password_check: true
+          horizon::disallow_iframe_embed: true
           horizon::cache_backend: django.core.cache.backends.memcached.MemcachedCache
           horizon::django_session_engine: 'django.contrib.sessions.backends.cache'
           horizon::vhost_extra_params: