LangSmith SDK: Streaming token events bypass output redaction

Description

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.

Recommendation

Update the langsmith package to the latest compatible version. Followings are version details:

• Affected version(s): <= 0.5.18
• Patched version(s): 0.5.19

References

• GHSA-rr7j-v2q5-chgv
• CVE-2026-41182
• CWE-200
• CWE-359
• CWE-532
• CAPEC-310
• OWASP 2021-A1
• OWASP 2021-A6
• OWASP 2021-A9

Related Issues

• LangSmith Client SDK Affected by Server-Side Request Forgery via Tracing Header Injection - CVE-2026-25528
• LangSmith SDK: Public prompt pull deserializes untrusted manifests without trust boundary warning - CVE-2026-45134
• LangSmith Client SDKs has Prototype Pollution in langsmith-sdk via Incomplete `__proto__` Guard in Internal lodash `set( - CVE-2026-40190
• Official Clerk JavaScript SDKs: Middleware-based route protection bypass - @clerk/nextjs - CVE-2026-41248

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Tags:

npm

langsmith