diff --git a/requirements.txt b/requirements.txt
index b6c8d67..34d8ab2 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -18,7 +18,7 @@ cryptography==2.1.4
 curtsies==0.2.11
 cycler==0.10.0
 docopt==0.6.2
-ecdsa==0.13
+ecdsa==0.13.3
 Events==0.3
 gevent==1.2.2
 greenlet==0.4.12
diff --git a/requirements_docs.txt b/requirements_docs.txt
index 1f29ded..edd1a86 100644
--- a/requirements_docs.txt
+++ b/requirements_docs.txt
@@ -22,7 +22,7 @@ curtsies==0.2.11
 cycler==0.10.0
 docopt==0.6.2
 docutils==0.14
-ecdsa==0.13
+ecdsa==0.13.3
 Events==0.3
 gevent==1.2.2
 greenlet==0.4.12