diff --git a/bec_lib/pyproject.toml b/bec_lib/pyproject.toml
index 4af2bf83..40733d70 100644
--- a/bec_lib/pyproject.toml
+++ b/bec_lib/pyproject.toml
@@ -19,7 +19,7 @@ dependencies = [
     "lmfit~=1.3",
     "loguru~=0.7",
     "louie~=2.0",
-    "msgpack~=1.0",
+    "msgpack~=1.0, >1.0.4",
     "numpy>=1.24, <3.0",
     "psutil~=5.9",
     "pydantic~=2.0",