diff --git a/requirements.txt b/requirements.txt
index a25826b..35316a3 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -2,3 +2,4 @@ furo
 sphinx
 sphinxcontrib-bibtex
 tabulate
+zipp>=3.19.1 # not directly required, pinned by Snyk to avoid a vulnerability