diff --git a/scripts/http-avaya-ipoffice-users.nse b/scripts/http-avaya-ipoffice-users.nse
index 81ab4e697..fca9857c5 100644
--- a/scripts/http-avaya-ipoffice-users.nse
+++ b/scripts/http-avaya-ipoffice-users.nse
@@ -62,7 +62,7 @@ action = function(host, port)
       local _, _, name = string.find(user_block, '<name>(.-)</name>')
       local _,_, fName = string.find(user_block, '<fname>(.-)</fname>')
       local _,_, ext = string.find(user_block, '<extn>(.-)</extn>')
-      stdnse.debug(1, string.format("User found!\nName: %s\nFull name: %s\nExt:%s", name, fName, ext))
+      stdnse.debug1("User found!\nName: %s\nFull name: %s\nExt:%s", name, fName, ext)
       if name ~= nil or fName ~= nil or ext ~= nil then 
         local user = {}
         user.name = name
diff --git a/scripts/http-shellshock.nse b/scripts/http-shellshock.nse
index 4bd90d4b4..625dbb164 100644
--- a/scripts/http-shellshock.nse
+++ b/scripts/http-shellshock.nse
@@ -90,13 +90,13 @@ function generate_http_req(host, port, uri, custom_header, cmd)
   local options = {header={}}
   options["no_cache"] = true
   if custom_header == nil then
-    stdnse.debug(1, string.format("Sending '%s' in HTTP headers:User-Agent,Cookie and Referer", cmd))
+    stdnse.debug1("Sending '%s' in HTTP headers:User-Agent,Cookie and Referer", cmd)
     options["header"]["User-Agent"] = cmd
     options["header"]["Referer"] = cmd
     options["header"]["Cookie"] = cmd
     options["header"][cmd] = cmd
   else
-    stdnse.debug(1, string.format("Sending '%s' in HTTP header '%s'", cmd, custom_header))
+    stdnse.debug1("Sending '%s' in HTTP header '%s'", cmd, custom_header)
     options["header"][custom_header] = cmd
   end
   local req = http.get(host, port, uri, options)
@@ -133,7 +133,7 @@ is executing commands injected via malicious HTTP headers.
         disclosure = {year = '2014', month = '09', day = '24'},
       },
     }
-    stdnse.debug(1, string.format("Random pattern '%s' was found in page. Host seems vulnerable.", rnd))
+    stdnse.debug1("Random pattern '%s' was found in page. Host seems vulnerable.", rnd)
     vuln.state = vulns.STATE.EXPLOIT
     if cmd ~= nil then
        req = generate_http_req(host, port, uri, http_header, cmd)