diff --git a/requirements.txt b/requirements.txt
index 554c67a..7880102 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,6 +1,6 @@
 atomicwrites==1.4.0
 attrs==21.2.0
-certifi==2021.5.30
+certifi==2022.9.14
 chainer==7.8.0
 chardet==4.0.0
 coverage==5.5