Sensitive output exposure via unredacted streaming events
Published Apr 23, 2026 · Updated Apr 23, 2026
Information exposure in LangChain LangSmith SDKs before JS 0.5.19 and Python 0.7.31 allows attackers to expose raw streamed output. The streaming paths append raw token values to new_token events, while prepareRunCreateOrUpdateInputs and _hide_run_outputs redact only run inputs and outputs. Exposure requires streaming with hideOutputs or hide_outputs enabled; the full content remains stored in LangSmith run events.
Summary
What happened
Information exposure in LangChain LangSmith SDKs before JS 0.5.19 and Python 0.7.31 allows attackers to expose raw streamed output. The streaming paths append raw token values to new_token events, while prepareRunCreateOrUpdateInputs and _hide_run_outputs redact only run inputs and outputs. Exposure requires streaming with hideOutputs or hide_outputs enabled; the full content remains stored in LangSmith run events.
The record
- CVE
- CVE-2026-41182
- Published
- Apr 23, 2026
- Updated
- Apr 23, 2026
- Vendor
- LangChain
- Product
- LangSmith SDK
- Classifications
- CWE-532, CWE-200, CWE-359
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 23, 2026CVE publishedPublication date reported by the CVE source.
- Apr 23, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=< 0.5.19
- Affected versionversion=< 0.7.31
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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