diff --git a/requirements.txt b/requirements.txt
index 76eda4d7c..0c42fdc47 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -3,3 +3,5 @@ mock==2.0.0
 rst2pdf
 six==1.10.0
 Sphinx==1.4.1
+pillow>=9.0.1 # not directly required, pinned by Snyk to avoid a vulnerability
+pygments>=2.7.4 # not directly required, pinned by Snyk to avoid a vulnerability