diff --git a/ncat/http.c b/ncat/http.c
index 0788ec253..16bfe32df 100644
--- a/ncat/http.c
+++ b/ncat/http.c
@@ -642,7 +642,7 @@ static const char *read_quoted_string(const char *s, char **quoted_string)
     }
     s++;
 
-    *quoted_string = buf;
+    *quoted_string = buf ? buf : Strdup("");
     return s;
 }
 
diff --git a/ncat/sys_wrap.c b/ncat/sys_wrap.c
index 934d7d736..0151d7d91 100644
--- a/ncat/sys_wrap.c
+++ b/ncat/sys_wrap.c
@@ -173,6 +173,8 @@ char *Strdup(const char *s)
 {
     char *ret;
 
+    if (s == NULL)
+        bye("Strdup argument must not be NULL");
     ret = strdup(s);
     if (ret == NULL)
         die("strdup");