diff --git a/requirements.txt b/requirements.txt
index 4abecc2..2660abc 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -3,3 +3,4 @@ numpy>=1.16.1
 scipy>=1.2.1
 matplotlib>=3.0.2
 xlrd>=1.2.0
+pillow>=10.3.0 # not directly required, pinned by Snyk to avoid a vulnerability