diff --git a/requirements-dev.txt b/requirements-dev.txt
index a2ebd84c58..9e883dfa47 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -19,3 +19,4 @@ sphinx-immaterial
 sphinxcontrib-spelling
 sphinx_autodoc_typehints
 wheel
+fonttools>=4.43.0 # not directly required, pinned by Snyk to avoid a vulnerability