diff --git a/requirements-test.txt b/requirements-test.txt
index 4e223a3f..16b0cbbd 100644
--- a/requirements-test.txt
+++ b/requirements-test.txt
@@ -8,3 +8,4 @@ pytest==3.2.5
 coverage
 pytest-expect>=1.1,<2.0
 mock
+zipp>=3.19.1 # not directly required, pinned by Snyk to avoid a vulnerability