diff --git a/doc/requirements.txt b/doc/requirements.txt
index 46c4f5d8b2..f184d9154a 100644
--- a/doc/requirements.txt
+++ b/doc/requirements.txt
@@ -8,3 +8,6 @@ reno>=3.1.0 # Apache-2.0
 os-api-ref>=1.0.0 # Apache-2.0
 python-keystoneclient!=2.1.0,>=2.0.0 # Apache-2.0
 sphinxcontrib-svg2pdfconverter>=0.1.0 # BSD
+requests>=2.32.2 # not directly required, pinned by Snyk to avoid a vulnerability
+urllib3>=2.2.2 # not directly required, pinned by Snyk to avoid a vulnerability
+zipp>=3.19.1 # not directly required, pinned by Snyk to avoid a vulnerability