diff --git a/docs/requirements.txt b/docs/requirements.txt
index ccab21128..1e99cf08a 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,3 +1,4 @@
 sphinx-rtd-theme
 sphinx
 recommonmark
+pygments>=2.7.4 # not directly required, pinned by Snyk to avoid a vulnerability