diff --git a/sys/src/requirements.txt b/sys/src/requirements.txt
index 42697f1..ba873a1 100644
--- a/sys/src/requirements.txt
+++ b/sys/src/requirements.txt
@@ -22,4 +22,4 @@ rsa==4.0
 six==1.12.0
 uritemplate==3.0.0
 urllib3==1.24.1
-Werkzeug==0.14.1
+Werkzeug==0.15.3