diff --git a/lib/techniques/blind/inference.py b/lib/techniques/blind/inference.py
index f82344196..8a4a743c6 100644
--- a/lib/techniques/blind/inference.py
+++ b/lib/techniques/blind/inference.py
@@ -48,6 +48,7 @@ from lib.core.threads import getCurrentThreadData
 from lib.core.threads import runThreads
 from lib.core.unescaper import unescaper
 from lib.request.connect import Connect as Request
+from lib.utils.xrange import xrange
 
 def bisection(payload, expression, length=None, charsetType=None, firstChar=None, lastChar=None, dump=False):
     """
@@ -197,9 +198,9 @@ def bisection(payload, expression, length=None, charsetType=None, firstChar=None
                 return result
 
             if charTbl is None:
-                charTbl = list(asciiTbl)
+                charTbl = type(asciiTbl)(asciiTbl)
 
-            originalTbl = list(charTbl)
+            originalTbl = type(asciiTbl)(charTbl)
 
             if continuousOrder and shiftTable is None:
                 # Used for gradual expanding into unicode charspace
@@ -269,7 +270,7 @@ def bisection(payload, expression, length=None, charsetType=None, firstChar=None
                             # list
                             if expand and shiftTable:
                                 charTbl = xrange(maxChar + 1, (maxChar + 1) << shiftTable.pop())
-                                originalTbl = list(charTbl)
+                                originalTbl = xrange(charTbl)
                                 maxChar = maxValue = charTbl[-1]
                                 minChar = minValue = charTbl[0]
                             else:
diff --git a/lib/utils/xrange.py b/lib/utils/xrange.py
new file mode 100644
index 000000000..de869448e
--- /dev/null
+++ b/lib/utils/xrange.py
@@ -0,0 +1,75 @@
+class xrange(object):
+    """
+    Advanced implementation of xrange (supports slice/copy/etc.)
+    Reference: http://code.activestate.com/recipes/521885-a-pythonic-implementation-of-xrange/
+    """
+
+    __slots__ = ['_slice']
+
+    def __init__(self, *args):
+        if args and isinstance(args[0], xrange):
+            self._slice = slice(args[0].start, args[0].stop, args[0].step)
+        else:
+            self._slice = slice(*args)
+        if self._slice.stop is None:
+            # slice(*args) will never put None in stop unless it was
+            # given as None explicitly.
+            raise TypeError("xrange stop must not be None")
+        
+    @property
+    def start(self):
+        if self._slice.start is not None:
+            return self._slice.start
+        return 0
+
+    @property
+    def stop(self):
+        return self._slice.stop
+
+    @property
+    def step(self):
+        if self._slice.step is not None:
+            return self._slice.step
+        return 1
+
+    def __hash__(self):
+        return hash(self._slice)
+
+    def __cmp__(self, other):
+        return (cmp(type(self), type(other)) or
+                cmp(self._slice, other._slice))
+
+    def __repr__(self):
+        return '%s(%r, %r, %r)' % (self.__class__.__name__,
+                                   self.start, self.stop, self.step)
+
+    def __len__(self):
+        return self._len()
+
+    def _len(self):
+        try:
+            return max(0, int((self.stop - self.start) / self.step))
+        except Exception, ex:
+            import pdb
+            pdb.set_trace()
+
+    def __getitem__(self, index):
+        if isinstance(index, slice):
+            start, stop, step = index.indices(self._len())
+            return xrange(self._index(start),
+                          self._index(stop), step*self.step)
+        elif isinstance(index, (int, long)):
+            if index < 0:
+                fixed_index = index + self._len()
+            else:
+                fixed_index = index
+                
+            if not 0 <= fixed_index < self._len():
+                raise IndexError("Index %d out of %r" % (index, self))
+            
+            return self._index(fixed_index)
+        else:
+            raise TypeError("xrange indices must be slices or integers")
+
+    def _index(self, i):
+        return self.start + self.step * i