diff --git a/kaitaistruct.py b/kaitaistruct.py
index 8edac81..cf47e0c 100644
--- a/kaitaistruct.py
+++ b/kaitaistruct.py
@@ -348,6 +348,8 @@ def process_xor_one(data, key):
     def process_xor_many(data, key):
         if key == b'\x00' * len(key):
             return data
+        if len(key) == 1:
+            return KaitaiStream.process_xor_one(data, ord(key))
 
         if PY2:
             return bytes(bytearray(a ^ b for a, b in zip(bytearray(data), itertools.cycle(bytearray(key)))))