langchain-ai langsmith-sdk pull_prompt/pull_prompt_commit deserialization

Summaryinfo

A vulnerability classified as critical has been found in langchain-ai langsmith-sdk. Affected is the function pull_prompt/pull_prompt_commit. Performing a manipulation results in deserialization. This vulnerability is cataloged as CVE-2026-45134. It is possible to initiate the attack remotely. There is no exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in langchain-ai langsmith-sdk (version now known). This affects the function pull_prompt/pull_prompt_commit. The manipulation with an unknown input leads to a deserialization vulnerability. CWE is classifying the issue as CWE-502. The product deserializes untrusted data without sufficiently verifying that the resulting data will be valid. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

LangSmith Client SDKs provide SDK's for interacting with the LangSmith platform. Prior to LangSmith SDK Python 0.8.0 and JS/TS 0.6.0, the LangSmith SDK's prompt pull methods (pull_prompt / pull_prompt_commit in Python, pullPrompt / pullPromptCommit in JS/TS) fetch and deserialize prompt manifests from the LangSmith Hub. These manifests may contain serialized LangChain objects and model configuration that affect runtime behavior. When pulling a public prompt by owner/name identifier, the manifest content is controlled by an external party, but prior versions of the SDK did not distinguish this from pulling a prompt within the caller's own organization. This vulnerability is fixed in LangSmith SDK Python 0.8.0 and JS/TS 0.6.0.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-45134 since 05/08/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit.

Upgrading eliminates this vulnerability.

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Productinfo

Type

• Artificial Intelligence Software

Vendor

• langchain-ai

Name

• langsmith-sdk

Website

• Product: https://github.com/langchain-ai/langsmith-sdk/

CPE 2.3info

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CPE 2.2info

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