diff --git a/server/core/modutil.cc b/server/core/modutil.cc
index 30acb0708..d9c4daa03 100644
--- a/server/core/modutil.cc
+++ b/server/core/modutil.cc
@@ -1447,7 +1447,7 @@ std::string get_canonical(GWBUF* querybuf)
         else if (*it == '\\')
         {
             // Jump over any escaped values
-            rval[i++] += *it++;
+            rval[i++] = *it++;
 
             if (it != buf.end())
             {