Patched code sample

import copy
import json
from typing import Any, Dict, List

# This example demonstrates the logic used to fix CVE-2026-41182.
# The vulnerability was that the 'hide_outputs' feature did not redact
# streaming 'new_token' events. The fix involves iterating through these
# events and redacting them, in addition to the final 'outputs' field.

REDACTED_VALUE = "[REDACTED]"

def _apply_output_redaction_fixed(run: Dict[str, Any]) -> Dict[str, Any]:
    """
    A representation of the fixed logic that redacts both the final run output
    and the intermediate streaming token events.

    This function simulates the patched behavior in the LangSmith SDK
    (version 0.7.31 and later).
    """
    # Create a copy to avoid modifying the original data in this example.
    run_copy = copy.deepcopy(run)

    # 1. Redact the final 'outputs' field (this part was already working).
    if "outputs" in run_copy and run_copy["outputs"] is not None:
        run_copy["outputs"] = REDACTED_VALUE

    # 2. THE FIX: Iterate through events and redact 'new_token' chunks.
    # The original vulnerable code skipped this entire block.
    events: List[Dict[str, Any]] = run_copy.get("events", [])
    for event in events:
        if event.get("name") == "new_token":
            # The sensitive token value is typically in event["kwargs"]["chunk"].
            if "kwargs" in event and isinstance(event["kwargs"], dict):
                if "chunk" in event["kwargs"]:
                    event["kwargs"]["chunk"] = REDACTED_VALUE
    return run_copy

# --- Demonstration ---

# Simulate a LangSmith run object containing sensitive data in streaming events.
# This data structure mimics what would be sent to the LangSmith platform.
run_with_sensitive_stream = {
    "name": "SensitiveDataQuery",
    "run_type": "llm",
    "inputs": {"prompt": "What is the secret access key?"},
    "outputs": {
        "generations": [{"text": "The secret key is sk-12345."}]
    },
    "events": [
        {"name": "start", "time": "...", "kwargs": {}},
        {"name": "new_token", "time": "...", "kwargs": {"chunk": "The "}},
        {"name": "new_token", "time": "...", "kwargs": {"chunk": "secret "}},
        {"name": "new_token", "time": "...", "kwargs": {"chunk": "key is "}},
        {"name": "new_token", "time": "...", "kwargs": {"chunk": "sk-12345."}},
        {"name": "end", "time": "...", "kwargs": {}},
    ],
}

# Apply the fixed redaction logic.
redacted_run_object = _apply_output_redaction_fixed(run_with_sensitive_stream)

# Print the result. Notice that the 'chunk' values in the 'new_token' events
# are now redacted, demonstrating the fix.
print(json.dumps(redacted_run_object, indent=2))