diff --git a/requirements.txt b/requirements.txt
index 002655b..7014c13 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -47,7 +47,7 @@ mock==2.0.0
 nbconvert==5.4.0
 nbformat==4.4.0
 networkx==2.2
-nltk==3.4
+nltk==3.4.5
 notebook==5.7.4
 numpy==1.15.4
 opencv-python==3.4.5.20