diff --git a/requirements.txt b/requirements.txt
index dfc4f32b9..c13effbd2 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -10,7 +10,7 @@ python-Levenshtein>=0.12.0
 pytz>=2018.9
 whatthepatch>=0.0.5
 icalevents==0.1.23
-icalendar==4.0.3
+icalendar==4.0.4
 sqlalchemy==1.3.10
 filelock==3.0.12
 alembic==1.3.0