diff --git a/requirements.txt b/requirements.txt
index 72f6c37..dbbaf50 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -76,7 +76,7 @@ six==1.10.0
 sympy==1.0
 tornado==4.4.2
 Twisted==16.0.0
-urllib3==1.13.1
+urllib3==1.26.5
 uTidylib==0.2
 wrapt==1.10.8
 zope.interface==4.1.3