LangSmith Client SDKs provide SDK's for interacting with the LangSmith platform. The LangSmith SDK's distributed tracing feature is vulnerable to Server-Side Request Forgery via malicious HTTP headers. An attacker can inject arbitrary api_url values through the baggage header, causing the SDK to exfiltrate sensitive trace data to attacker-controlled endpoints. When using distributed tracing, the SDK parses incoming HTTP headers via RunTree.from_headers() in Python or RunTree.fromHeaders() in Typescript. The baggage header can contain replica configurations including api_url and api_key fields. Prior to the fix, these attacker-controlled values were accepted without validation. When a traced operation completes, the SDK's post() and patch() methods send run data to all configured replica URLs, including any injected by an attacker. This vulnerability is fixed in version 0.6.3 of the Python SDK and 0.4.6 of the JavaScript SDK.

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - LangSmith Client SDKs provide SDK's for interacting with the LangSmith platform. The LangSmith SDK's
    distributed tracing feature is vulnerable to Server-Side Request Forgery via malicious HTTP headers. An
    attacker can inject arbitrary api_url values through the baggage header, causing the SDK to exfiltrate
    sensitive trace data to attacker-controlled endpoints. When using distributed tracing, the SDK parses
    incoming HTTP headers via RunTree.from_headers() in Python or RunTree.fromHeaders() in Typescript. The
    baggage header can contain replica configurations including api_url and api_key fields. Prior to the fix,
    these attacker-controlled values were accepted without validation. When a traced operation completes, the
    SDK's post() and patch() methods send run data to all configured replica URLs, including any injected by
    an attacker. This vulnerability is fixed in version 0.6.3 of the Python SDK and 0.4.6 of the JavaScript
    SDK. (CVE-2026-25528)

ID	Name	Product	Family	Type	Severity
464666	Echo: langsmith: security update to 0.4.6	Tenable Cloud Security	Echo Local Security Checks	Local	medium
464666	Echo: langsmith: security update to 0.4.6	Tenable Self-Hosted Container Security	Echo Local Security Checks	Local	medium
437670	SCA: security update for langsmith (GHSA-v34v-rq6j-cj6p)	Tenable Cloud Security	SCA Checks	Local	medium
437670	SCA: security update for langsmith (GHSA-v34v-rq6j-cj6p)	Tenable Self-Hosted Container Security	SCA Checks	Local	medium

Detections

Analytics

CVE-2026-25528

medium

Tenable Plugins

medium

medium

medium

medium