diff --git a/backend/requirements/default.txt b/backend/requirements/default.txt
index 979f112d6fa..acc41b3f616 100644
--- a/backend/requirements/default.txt
+++ b/backend/requirements/default.txt
@@ -32,7 +32,7 @@ litellm==1.43.18
 llama-index==0.9.45
 Mako==1.2.4
 msal==1.28.0
-nltk==3.8.1
+nltk==3.9
 Office365-REST-Python-Client==2.5.9
 oauthlib==3.2.2
 openai==1.41.1