diff --git a/requirements.txt b/requirements.txt
index 9e6d6b6..a539326 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -3,3 +3,4 @@ packaging>=20.4
 permit-broadcaster[redis,postgres,kafka]>=0.2.5,<3
 pydantic>=1.9.1
 websockets>=10.3
+zipp>=3.19.1 # not directly required, pinned by Snyk to avoid a vulnerability