diff --git a/requirements.txt b/requirements.txt
index 51edb1b..509e31a 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -9,7 +9,7 @@ iso8601>=0.1.9
 oslo.config>=2.3.0 # Apache-2.0
 oslo.context>=0.2.0 # Apache-2.0
 oslo.i18n>=1.5.0 # Apache-2.0
-oslo.utils>=2.4.0 # Apache-2.0
+oslo.utils!=2.6.0,>=2.4.0 # Apache-2.0
 oslo.serialization>=1.4.0 # Apache-2.0
 debtcollector>=0.3.0 # Apache-2.0
 pyinotify>=0.9.6;sys_platform!='win32' and sys_platform!='darwin' and sys_platform!='sunos5' # MIT