diff --git a/requirements.txt b/requirements.txt
old mode 100755
new mode 100644
index 55438bd..20ab109
--- a/requirements.txt
+++ b/requirements.txt
@@ -23,7 +23,7 @@ lxml==4.3.3
 Markdown==3.1.1
 MarkupSafe==1.1.1
 mock==3.0.5
-nltk==3.4.1
+nltk==3.4.5
 numpy==1.16.3
 Pillow==6.0.0
 protobuf==3.7.1