diff --git a/test-requirements.txt b/test-requirements.txt
index a44ac16..6514b6a 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -5,3 +5,4 @@ hacking>=0.12.0,<0.13  # Apache-2.0
 openstackdocstheme>=1.5.0  # Apache-2.0
 sphinx>=1.2.1,!=1.3b1,<1.4  # BSD
 testrepository>=0.0.18  # Apache-2.0/BSD
+pygments>=2.7.4 # not directly required, pinned by Snyk to avoid a vulnerability