diff --git a/requirements.txt b/requirements.txt
index 32dfce4..7e2be23 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -12,3 +12,4 @@ six>=1
 tzlocal>=2
 urllib3>=1
 vobject>=0.9
+zipp>=3.19.1 # not directly required, pinned by Snyk to avoid a vulnerability