diff --git a/sins/run.py b/sins/run.py
index 93b0e5f..3fc305f 100755
--- a/sins/run.py
+++ b/sins/run.py
@@ -84,6 +84,12 @@ def sins():
         with seed.open('rb') as seed_file:
             seed_data = seed_file.read()
 
+    seed_data = bytearray(seed_data)
+
+    offset = randint(0, len(seed_data))
+    flip = randint(0, 255)
+    seed_data[offset] ^= flip
+
     seed_len = ctypes.c_uint(len(seed_data))
     logger.info(f'seed_data\n{binascii.b2a_hex(seed_data)}')
     logger.info(f'seed_len: {seed_len}')