diff --git a/setup.cfg b/setup.cfg
index 73765697..244e3cc8 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -27,7 +27,7 @@ packages =
 kerberos =
   requests-kerberos>=0.6 # ISC
 saml2 =
-  lxml>=2.3 # BSD
+  lxml!=3.7.0,>=2.3 # BSD
 oauth1 =
   oauthlib>=0.6 # BSD
 betamax =