LangSmith Client SDKs provide SDK's for interacting with the LangSmith platform.
Date: 2026-05
Attack vector: deserialization
Category: vulnerability-disclosure
Severity: High
CVE: CVE-2026-41182
CVE-2026-45134
CWE: CWE-200
CWE-359
CWE-502
CWE-532
CVSS: 7.1 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N)

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.


Mitigations:

Architectural layers (MAESTRO):