langsmith

CVE-2026-41182

CVE-2026-41182 is a medium-severity security vulnerability in langsmith (npm), affecting versions <= 0.5.18. It is fixed in 0.5.19, 0.7.31.

Key facts
CVSS score
5.3
Medium
Attack vector
Network
Issuing authority
GitHub Advisory Database
Affected package
langsmith
Fixed in
0.5.19, 0.7.31
Disclosed
2026

Summary

Summary The LangSmith SDK's output redaction controls (hideOutputs in JS, hideoutputs in Python) do not apply to streaming token events. When an LLM run produces streaming output, each chunk is recorded as a newtoken event containing the raw token value. These events bypass the redaction pipeline entirely, prepareRunCreateOrUpdateInputs (JS) and hiderunoutputs (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. Details Both JS and Python SDKs are affected. The same pattern exists in both: JS SDK: traceable.ts:997-1003 and traceable.ts:1044-1050 Python SDK: runhelpers.py:1924 and runhelpers.py:1996 In both SDKs, newtoken events with raw kwargs.token values are added during streaming, and the redaction pipeline (hideOutputs in JS, hide_outputs in Python) only processes inputs/outputs, never events.

Impact

Severity and exposure

CVE-2026-41182 has a CVSS score of 5.3 (Medium). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment.

A fixed version is available (0.5.19, 0.7.31). Upgrading removes the vulnerable code path.

Affected versions

npm

  • langsmith (<= 0.5.18)

pip

  • langsmith (<= 0.7.30)

Security releases

  • langsmith → 0.5.19 (npm)
  • langsmith → 0.7.31 (pip)
Kodem intelligence

Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.

Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter instead of chasing every advisory.

Kodem's runtime-powered SCA identifies whether CVE-2026-41182 is reachable in your applications. Explore open-source security for your team.

See if CVE-2026-41182 is reachable in your applications. Get a demo

Already deployed Kodem? See CVE-2026-41182 in your environment

Remediation advice

Upgrade the following packages to resolve this vulnerability:

  • Upgrade langsmith to 0.5.19 or later
  • Upgrade langsmith to 0.7.31 or later

Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.

Frequently asked questions about CVE-2026-41182

What is CVE-2026-41182?

CVE-2026-41182 is a medium-severity security vulnerability in langsmith (npm), affecting versions <= 0.5.18. It is fixed in 0.5.19, 0.7.31.

How severe is CVE-2026-41182?

CVE-2026-41182 has a CVSS score of 5.3 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.

Which versions of langsmith are affected by CVE-2026-41182?

langsmith (npm) versions <= 0.5.18 is affected.

Is there a fix for CVE-2026-41182?

Yes. CVE-2026-41182 is fixed in 0.5.19, 0.7.31. Upgrade to this version or later.

Is CVE-2026-41182 exploitable, and should I be worried?

Whether CVE-2026-41182 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo

What actually determines whether CVE-2026-41182 is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

How do I fix CVE-2026-41182?
  • Upgrade langsmith to 0.5.19 or later
  • Upgrade langsmith to 0.7.31 or later

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