diff --git a/examples/redteam-langchain/requirements.txt b/examples/redteam-langchain/requirements.txt
index f00aaac4892a..dece6b2b19d6 100644
--- a/examples/redteam-langchain/requirements.txt
+++ b/examples/redteam-langchain/requirements.txt
@@ -23,7 +23,7 @@ langchain-core==0.3.30
 langchain-openai==0.3.0
 langchain-text-splitters==0.3.5
 langsmith==0.2.11
-marshmallow==3.25.1
+marshmallow==3.26.2
 multidict==6.1.0
 mypy-extensions==1.0.0
 numpy==2.2.1