diff --git a/core/setup.py b/core/setup.py
index d27da9a2fbe..7da702f0dda 100644
--- a/core/setup.py
+++ b/core/setup.py
@@ -51,7 +51,7 @@
         # Pin to the patch or minor version, and bump in each new minor version of dbt-core.
         "agate>=1.7.0,<1.10",
         "Jinja2>=3.1.3,<4",
-        "mashumaro[msgpack]>=3.9,<4.0",
+        "mashumaro[msgpack]>=3.9,<3.15",
         # ----
         # dbt-core uses these packages in standard ways. Pin to the major version, and check compatibility
         # with major versions in each new minor version of dbt-core.