diff --git a/requirements.txt b/requirements.txt
index 2e384d1..19a7b66 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,5 +1,5 @@
 bokeh==1.0.4
 numpy==1.16.2
 flask==1.0.2
-flask_cors==3.0.7
+flask_cors==3.0.9
 sympy==1.4