diff --git a/container_recipes/soft-matter/conf/python/requirements.txt b/container_recipes/soft-matter/conf/python/requirements.txt
index b9c2aa0..442c578 100644
--- a/container_recipes/soft-matter/conf/python/requirements.txt
+++ b/container_recipes/soft-matter/conf/python/requirements.txt
@@ -338,7 +338,7 @@ Twisted
 twine
 typed-ast
 typing-extensions
-ujson==1.35
+ujson==5.12.1
 Unidecode
 urllib3
 versioneer