diff --git a/proj/requirements.txt b/proj/requirements.txt
index 02b66af..61ee76f 100644
--- a/proj/requirements.txt
+++ b/proj/requirements.txt
@@ -13,3 +13,4 @@ apispec-webframeworks
 tox
 celery[redis]>=5.0.0
 gunicorn
+filelock>=3.20.1 # not directly required, pinned by Snyk to avoid a vulnerability