diff --git a/python-oauthlib.spec b/python-oauthlib.spec
index 50c6f53..9ca1eaf 100644
--- a/python-oauthlib.spec
+++ b/python-oauthlib.spec
@@ -27,11 +27,11 @@ BuildRequires:      python2-devel
 BuildRequires:      python-setuptools
 
 BuildRequires:      python-nose
-BuildRequires:      python-crypto
+BuildRequires:      python-crypto >= 2.6
 BuildRequires:      python-unittest2
 BuildRequires:      python-mock
 
-Requires:           python-crypto
+Requires:           python-crypto >= 2.6
 
 
 %if 0%{?with_python3}
@@ -39,7 +39,7 @@ BuildRequires:      python3-devel
 BuildRequires:      python3-setuptools
 
 BuildRequires:      python3-nose
-BuildRequires:      python3-crypto
+BuildRequires:      python3-crypto >= 2.6
 BuildRequires:      python3-mock
 %endif
 
@@ -56,7 +56,7 @@ very little effort.
 Summary:            An implementation of the OAuth request-signing logic
 Group:              Development/Libraries
 
-Requires:           python3-crypto
+Requires:           python3-crypto >= 2.6
 
 %description -n python3-oauthlib
 OAuthLib is a generic utility which implements the logic of OAuth without