--- nmap/nping/utils.cc	2010-05-24 03:29:45.110203434 -0500
+++ nmap-my-branch/nping/utils.cc	2010-05-26 05:29:20.085931466 -0500
@@ -177,23 +177,33 @@
  static u8 dst[16384];
  size_t dstlen=16384;
  unsigned int i=0, j=0;
+ char *start=NULL;
 
   if(str==NULL || outlen==NULL)
     return NULL;
 
- memset(auxbuff,0,1024);
+  /* This catches the empty string possibility "" */
+  if(strlen(str) == 0)
+    return NULL;
+
+   memset(auxbuff,0,1024);
 
-  char *start=NULL;
 
   /* String should be treated as a hex number in this format: 0xAABBCCDDEE...
-   * He process it the way it is specified, we don't perform byte order
+   * We process it the way it is specified, we don't perform byte order
    * conversions so if the users says 0x00AA we write dst[0]=0x00, dst[1]==0xAA
    * no matter the endianness of the host system. */
   if( !strncmp("0x", str, 2) ){
+     /* This catches the case of an empty "0x" */
+     if(strlen(str) == 2)
+        return NULL;
      start=str+2;
   }
   /* String should be treated as list of hex char in this format: \x00\xFF\x0A*/
-  else if( !strncmp("\\x", str, 1) ){
+  else if( !strncmp("\\x", str, 2) ){
+    /* This catches the case of an empty "\x" */
+    if(strlen(str) == 2)
+      return NULL;
     /* Copy all interesting bytes to an aux array, discard "\x" */  
     for(i=0; i<strlen(str) && j<1023; i++){
         if( str[i]!='\\' && str[i]!='x' && str[i]!='X')