diff --git a/requirements/test_requirements_py27.txt b/requirements/test_requirements_py27.txt
index 7a5fe9679..4ffe5156d 100644
--- a/requirements/test_requirements_py27.txt
+++ b/requirements/test_requirements_py27.txt
@@ -22,3 +22,4 @@ suds-jurko
 zeep
 numpy<1.16.99
 pandas<0.24.99
+waitress>=3.0.1 # not directly required, pinned by Snyk to avoid a vulnerability