diff --git a/requirements.txt b/requirements.txt
index 022d17b..f1dc8ac 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -21,7 +21,7 @@ google-resumable-media==0.3.2
 googleapis-common-protos==1.5.9
 grpcio==1.19.0
 gunicorn==19.9.0
-httplib2==0.12.1
+httplib2==0.18.0
 idna==2.8
 jws==0.1.3
 msgpack==0.6.1