diff --git a/requirements.txt b/requirements.txt
index 207d720..154071d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -9,7 +9,7 @@ google-auth==1.6.3
 google-auth-httplib2==0.0.3
 google-auth-oauthlib==0.4.0
 gunicorn==19.9.0
-httplib2==0.13.1
+httplib2==0.18.0
 idna==2.8
 itsdangerous==1.1.0
 Jinja2==2.10.1