CVE-2026-40190

LangSmith Client SDKs provide SDK's for interacting with the LangSmith platform. Prior to 0.5.18, the LangSmith JavaScript/TypeScript SDK (langsmith) contains an incomplete prototype pollution fix in its internally vendored lodash set() utility. The baseAssignValue() function only guards against the __proto__ key, but fails to prevent traversal via constructor.prototype. This allows an attacker who controls keys in data processed by the createAnonymizer() API to pollute Object.prototype, affecting all objects in the Node.js process. This vulnerability is fixed in 0.5.18.
Configurations

No configuration.

History

10 Apr 2026, 20:16

Type Values Removed Values Added
New CVE

Information

Published : 2026-04-10 20:16

Updated : 2026-05-29 16:14


NVD link : CVE-2026-40190

Mitre link : CVE-2026-40190

CVE.ORG link : CVE-2026-40190


JSON object : View

Products Affected

No product.

CWE
CWE-1321

Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')