diff --git a/requirements.txt b/requirements.txt
index 8b5a694..cee12d2 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -9,3 +9,4 @@ antlr4-python3-runtime==4.9.2
 multipledispatch==0.6.0
 bandit==1.7.0
 flake8==3.9.2
+zipp>=3.19.1 # not directly required, pinned by Snyk to avoid a vulnerability