diff --git a/pysaunter/requirements.txt b/pysaunter/requirements.txt
index 40d6431..6f124d5 100644
--- a/pysaunter/requirements.txt
+++ b/pysaunter/requirements.txt
@@ -6,7 +6,7 @@ Pygments==1.6
 Sphinx==1.2.2
 browsermob-proxy==0.5.0
 docutils==0.11
-ecdsa==0.10
+ecdsa==0.13.3
 execnet==1.1
 httplib2==0.8
 ipython==1.1.0