diff --git a/requirements.txt b/requirements.txt
index 9088d67..9092cf7 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -40,7 +40,7 @@ mccabe==0.6.1
 mistune==0.8.4
 nbconvert==5.4.0
 nbformat==4.4.0
-nltk==3.4
+nltk==3.4.5
 notebook==5.7.4
 numpy==1.16.0
 olefile==0.46