diff --git a/docs/photos.rst b/docs/photos.rst
index deea181..df5b5dc 100644
--- a/docs/photos.rst
+++ b/docs/photos.rst
@@ -10,6 +10,14 @@ Configure which file is used as default photo :
 
     $default_photo = "images/240px-PICA.jpg";
 
+Photo endpoint
+--------------
+
+A user's photo can be queried on ``/photo.php?dn=[user's DN]``. An additionnal
+``no_fallback`` parameter can be passed to avoid falling back to a default
+picture and returning 404: ``/photo.php?no_fallback&dn=[user's DN]``. This is
+useful to eg. use an application's internal fallback image instead.
+
 LDAP attribute
 --------------
 
diff --git a/htdocs/photo.php b/htdocs/photo.php
index 4205f4f..c5106f7 100644
--- a/htdocs/photo.php
+++ b/htdocs/photo.php
@@ -74,8 +74,14 @@
     $result = "dnrequired";
 }
 
-# Display default photo if any error
 if ( !$photo ) {
+    # If `no_fallback` in GET parameters, fail with 404
+    if(isset($_GET['no_fallback'])) {
+        http_response_code(404);
+        die();
+    }
+
+    # Else, display default photo if any error
     $photo = imagecreatefromjpeg($default_photo);
 }