diff --git a/requirements.txt b/requirements.txt
index d897794..ddda718 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,4 @@
-pbr>=0.5.21,<1.0
+pbr>=0.6,!=0.7,<1.0
 argparse
 icalendar
 pyyaml