diff --git a/requirements.txt b/requirements.txt
index 03e0b4bd8a..4b46b0984c 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -3,7 +3,7 @@
 # process, which may cause wedges in the gate later.
 
 dnspython>=1.14.0;python_version=='2.7'  # http://www.dnspython.org/LICENSE
-eventlet>=0.17.4  # MIT
+eventlet>=0.17.4,!=0.23.0  # MIT
 greenlet>=0.3.1
 netifaces>=0.5,!=0.10.0,!=0.10.1
 PasteDeploy>=1.3.3