diff --git a/books/blackhat_python/requirements.txt b/books/blackhat_python/requirements.txt
old mode 100755
new mode 100644
index 3081020..9c88add
--- a/books/blackhat_python/requirements.txt
+++ b/books/blackhat_python/requirements.txt
@@ -1,7 +1,7 @@
 certifi==2019.11.28
 cffi==1.14.0
 chardet==3.0.4
-cryptography==2.9
+cryptography==39.0.1
 github3.py==1.3.0
 idna==2.9
 jwcrypto==0.7