fix(logging): scrub callback config params to prevent credential leak in Langfuse and other loggers

- Add scrub_callback_config_params_from_dict using _supported_callback_params
- Apply at litellm_logging layer so all callbacks (Langfuse, Langsmith, etc.) are protected
- Remove Langfuse-specific filter; fix is now centralized
- Add test_scrub_callback_config_params_removes_credentials
- Add before/after screenshots showing secret leak fixed

Made-with: Cursor

litellm/integrations/langfuse/langfuse.py

@@ -20,16 +20,16 @@ from packaging.version import Version
 import litellm
 from litellm._logging import verbose_logger
 from litellm.constants import MAX_LANGFUSE_INITIALIZED_CLIENTS
-from litellm.litellm_core_utils.core_helpers import (
-    safe_deep_copy,
-    reconstruct_model_name,
-    filter_exceptions_from_params,
-)
-from litellm.litellm_core_utils.redact_messages import redact_user_api_key_info
 from litellm.integrations.langfuse.langfuse_mock_client import (
     create_mock_langfuse_client,
     should_use_langfuse_mock,
 )
+from litellm.litellm_core_utils.core_helpers import (
+    filter_exceptions_from_params,
+    reconstruct_model_name,
+    safe_deep_copy,
+)
+from litellm.litellm_core_utils.redact_messages import redact_user_api_key_info
 from litellm.llms.custom_httpx.http_handler import _get_httpx_client
 from litellm.secret_managers.main import str_to_bool
 from litellm.types.integrations.langfuse import *
@@ -272,7 +272,9 @@ class LangFuseLogger:
         """
         try:
             verbose_logger.debug(
-                f"Langfuse Logging - Enters logging function for model {kwargs}"
+                "Langfuse Logging - Enters logging function for model call_type=%s litellm_call_id=%s",
+                kwargs.get("call_type"),
+                kwargs.get("litellm_call_id"),
             )
 
             # set default values for input/output for langfuse logging

litellm/litellm_core_utils/initialize_dynamic_callback_params.py

@@ -1,36 +1,60 @@
 from typing import Dict, Optional
+
 from litellm.secret_managers.main import get_secret_str
 from litellm.types.utils import StandardCallbackDynamicParams
 
-# Hardcoded list of supported callback params to avoid runtime inspection issues with TypedDict
+# Callback config params - never send to external loggers (credential leak)
+_SUPPORTED_CALLBACK_PARAMS_FROZEN = frozenset(
+    [
+        "langfuse_public_key",
+        "langfuse_secret",
+        "langfuse_secret_key",
+        "langfuse_host",
+        "langfuse_prompt_version",
+        "gcs_bucket_name",
+        "gcs_path_service_account",
+        "langsmith_api_key",
+        "langsmith_project",
+        "langsmith_base_url",
+        "langsmith_sampling_rate",
+        "langsmith_tenant_id",
+        "humanloop_api_key",
+        "arize_api_key",
+        "arize_space_key",
+        "arize_space_id",
+        "posthog_api_key",
+        "posthog_host",
+        "braintrust_api_key",
+        "braintrust_project",
+        "braintrust_host",
+        "slack_webhook_url",
+        "lunary_public_key",
+        "turn_off_message_logging",
+        "litellm_logging_obj",
+        "environment_variables",
+    ]
+)
+
+# List form for iteration (excludes litellm_logging_obj, environment_variables - config only)
 _supported_callback_params = [
-    "langfuse_public_key",
-    "langfuse_secret",
-    "langfuse_secret_key",
-    "langfuse_host",
-    "langfuse_prompt_version",
-    "gcs_bucket_name",
-    "gcs_path_service_account",
-    "langsmith_api_key",
-    "langsmith_project",
-    "langsmith_base_url",
-    "langsmith_sampling_rate",
-    "langsmith_tenant_id",
-    "humanloop_api_key",
-    "arize_api_key",
-    "arize_space_key",
-    "arize_space_id",
-    "posthog_api_key",
-    "posthog_host",
-    "braintrust_api_key",
-    "braintrust_project",
-    "braintrust_host",
-    "slack_webhook_url",
-    "lunary_public_key",
-    "turn_off_message_logging",
+    p for p in _SUPPORTED_CALLBACK_PARAMS_FROZEN if p not in ("litellm_logging_obj", "environment_variables")
 ]
 
 
+def scrub_callback_config_params_from_dict(data: Dict) -> Dict:
+    if not data:
+        return data
+    keys_to_remove = [
+        k for k in data
+        if k in _SUPPORTED_CALLBACK_PARAMS_FROZEN
+        or k.endswith("_secret_key")
+        or k.endswith("_secret")
+        or k.endswith("_api_key")
+    ]
+    result = {k: v for k, v in data.items() if k not in keys_to_remove}
+    return result
+
+
 def initialize_standard_callback_dynamic_params(
     kwargs: Optional[Dict] = None,
 ) -> StandardCallbackDynamicParams:

litellm/litellm_core_utils/litellm_logging.py

@@ -61,6 +61,9 @@ from litellm.integrations.mlflow import MlflowLogger
 from litellm.integrations.sqs import SQSLogger
 from litellm.litellm_core_utils.core_helpers import reconstruct_model_name
 from litellm.litellm_core_utils.get_litellm_params import get_litellm_params
+from litellm.litellm_core_utils.initialize_dynamic_callback_params import (
+    scrub_callback_config_params_from_dict,
+)
 from litellm.litellm_core_utils.llm_cost_calc.tool_call_cost_tracking import (
     StandardBuiltInToolCostTracking,
 )
@@ -537,11 +540,14 @@ class Logging(LiteLLMLoggingBaseClass):
         if _is_debugging_on() or self.litellm_request_debug:
             verbose_logger.debug(f"self.optional_params: {self.optional_params}")
 
+        sanitized_optional_params = scrub_callback_config_params_from_dict(
+            dict(optional_params)
+        )
         self.model_call_details.update(
             {
                 "model": self.model,
                 "messages": self.messages,
-                "optional_params": self.optional_params,
+                "optional_params": sanitized_optional_params,
                 "litellm_params": self.litellm_params,
                 "start_time": self.start_time,
                 "stream": self.stream,
@@ -550,7 +556,7 @@ class Logging(LiteLLMLoggingBaseClass):
                 "litellm_call_id": self.litellm_call_id,
                 "completion_start_time": self.completion_start_time,
                 "standard_callback_dynamic_params": self.standard_callback_dynamic_params,
-                **self.optional_params,
+                **sanitized_optional_params,
                 **additional_params,
             }
         )

tests/logging_callback_tests/test_dynamic_otel_keys.py

@@ -5,6 +5,7 @@ sys.path.insert(0, os.path.abspath("../.."))
 
 from litellm.litellm_core_utils.initialize_dynamic_callback_params import (
     initialize_standard_callback_dynamic_params,
+    scrub_callback_config_params_from_dict,
 )
 
 
@@ -47,6 +48,24 @@ def test_dynamic_key_extraction_from_litellm_params_metadata():
     assert params.get("langfuse_secret_key") == "sk-litellm"
 
 
+def test_scrub_callback_config_params_removes_credentials():
+    """Scrub removes callback config/credentials before passing to loggers."""
+    data = {
+        "messages": "[{'role': 'user', 'content': 'Hi'}]",
+        "langfuse_public_key": "pk-lf-xxx",
+        "langfuse_secret": "sk-lf-4be1b432-61f4-4771-82a2-a33d3822ad65",
+        "langfuse_host": "http://localhost:9999",
+        "litellm_logging_obj": "<Logging object>",
+    }
+    result = scrub_callback_config_params_from_dict(data)
+    assert "messages" in result
+    assert "langfuse_secret" not in result
+    assert "langfuse_public_key" not in result
+    assert "langfuse_host" not in result
+    assert "litellm_logging_obj" not in result
+
+
 if __name__ == "__main__":
     test_dynamic_key_extraction_from_metadata()
     test_dynamic_key_extraction_from_litellm_params_metadata()
+    test_scrub_callback_config_params_removes_credentials()