CVE-2026-45134
LangSmith Client SDK: Public prompt pull deserializes untrusted manifests without trust boundary warning
- State
- Published
- Severity
- 7.1 High
- Published
- May 27, 2026
- Updated
- Jun 2, 2026
- Reserved
- May 8, 2026
Description
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 7.1 High | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N | GitHub_M |
Weaknesses
- CWE-502 Deserialization of Untrusted Data
Affected Products
| Product | Versions |
|---|---|
langsmith-sdklangchain-ai |
|
References
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