diff --git a/CHANGELOG.md b/CHANGELOG.md
index ed34214d17..0ead2897a4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -17,6 +17,10 @@ Changes are grouped as follows
 - `Fixed` for any bug fixes.
 - `Security` in case of vulnerabilities.
 
+## [6.38.1] - 2023-10-31
+### Fixed
+- `onFailure` property in Workflows was expected as mandatory and was raising KeyError if it was not returnd by the API. The sdk now assumes the field to be optional loads it as None instead of raising an error.
+
 ## [6.38.0] - 2023-10-30
 ### Added
 - Support `onFailure` property in Workflows, allowing marking Tasks as optional in a Workflow.
@@ -37,9 +41,9 @@ Changes are grouped as follows
 
 ## [6.34.2] - 2023-10-23
 ### Fixed
-- Loading a `ContainerApply` from source failed with `KeyError` if `nullable`, `autoIncrement`, or `cursorable` were not set 
-  in the `ContainerProperty` and `BTreeIndex` classes even though they are optional. This is now fixed. 
- 
+- Loading a `ContainerApply` from source failed with `KeyError` if `nullable`, `autoIncrement`, or `cursorable` were not set
+  in the `ContainerProperty` and `BTreeIndex` classes even though they are optional. This is now fixed.
+
 ## [6.34.1] - 2023-10-23
 ### Added
 - Support for setting `data_set_id` and `metadata` in `ThreeDModelsAPI.create`.
diff --git a/cognite/client/_version.py b/cognite/client/_version.py
index 4c1be1e765..84b2ae4f40 100644
--- a/cognite/client/_version.py
+++ b/cognite/client/_version.py
@@ -1,4 +1,4 @@
 from __future__ import annotations
 
-__version__ = "6.38.0"
+__version__ = "6.38.1"
 __api_subversion__ = "V20220125"
diff --git a/cognite/client/data_classes/workflows.py b/cognite/client/data_classes/workflows.py
index 5b82e6a12e..e2e3995338 100644
--- a/cognite/client/data_classes/workflows.py
+++ b/cognite/client/data_classes/workflows.py
@@ -382,7 +382,7 @@ def _load(cls, resource: dict | str, cognite_client: CogniteClient | None = None
             # Allow default to come from the API.
             retries=resource.get("retries"),  # type: ignore[arg-type]
             timeout=resource.get("timeout"),  # type: ignore[arg-type]
-            on_failure=resource["onFailure"],
+            on_failure=resource.get("onFailure"),  # type: ignore[arg-type]
             depends_on=[dep["externalId"] for dep in resource.get("dependsOn", [])] or None,
         )
 
diff --git a/pyproject.toml b/pyproject.toml
index 2bbe2354b3..728ad2267f 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,7 +1,7 @@
 [tool.poetry]
 name = "cognite-sdk"
 
-version = "6.38.0"
+version = "6.38.1"
 description = "Cognite Python SDK"
 readme = "README.md"
 documentation = "https://cognite-sdk-python.readthedocs-hosted.com"