diff --git a/requirements.txt b/requirements.txt
index 916049f..ae5ae68 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -3,7 +3,7 @@ chardet==3.0.4
 coverage==4.5.3
 coveralls==1.7.0
 docopt==0.6.2
-ecdsa==0.13.2
+ecdsa==0.13.3
 httmock==1.3.0
 idna==2.8
 nose==1.3.7