diff --git a/docs/requirements.txt b/docs/requirements.txt
index 02deecdb..fb4b6550 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,2 +1,3 @@
 breathe
 sphinx-rtd-theme
+urllib3>=2.5.0 # not directly required, pinned by Snyk to avoid a vulnerability