diff --git a/ci/requirements-3.4_64.txt b/ci/requirements-3.4_64.txt
index f2a364ed64311..efb3ac28162ec 100644
--- a/ci/requirements-3.4_64.txt
+++ b/ci/requirements-3.4_64.txt
@@ -8,3 +8,4 @@ scipy
 numexpr
 pytables
 matplotlib
+pillow>=10.2.0 # not directly required, pinned by Snyk to avoid a vulnerability