diff --git a/requirements.txt b/requirements.txt
index 5a1eeec..87c34b6 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -14,7 +14,7 @@ idna==2.6
 lru-dict==1.1.6
 parsimonious==0.8.0
 psutil==5.6.6
-pycryptodome==3.6.1
+pycryptodome==3.6.6
 PyYAML==3.12
 requests==2.18.4
 rlp==1.0.1