add_action('add_attachment', 'create_post');
function create_post( $attach_ID ) {
$attachment = get_post( $attach_ID );
$my_post_data = array(
'post_title' => $attachment->post_title,
'post_type' => 'post',
'post_category' => array('0'),
'post_status' => 'publish'
);
$post_id = wp_insert_post( $my_post_data );
// attach media to post
wp_update_post( array(
'ID' => $attach_ID,
'post_parent' => $post_id,
) );
set_post_thumbnail( $post_id, $attach_ID );
return $attach_ID;
}