diff --git a/requirements.txt b/requirements.txt
index f48c52b..3c92423 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -9,7 +9,7 @@ chardet==3.0.4
 Click==7.0
 cryptography==2.4.2
 dominate==2.3.5
-ecdsa==0.13
+ecdsa==0.13.3
 Flask==1.0.2
 Flask-APScheduler==1.11.0
 Flask-Admin==1.5.3