LangSmith Client SDK Affected by Server-Side Request Forgery via Tracing Header Injection

Description

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.

Recommendation

Update the langsmith package to the latest compatible version. Followings are version details:

• Affected version(s): >= 0.3.41, < 0.4.6
• Patched version(s): 0.4.6

References

• GHSA-v34v-rq6j-cj6p
• CVE-2026-25528
• CWE-918
• CAPEC-310
• OWASP 2021-A10
• OWASP 2021-A6

Related Issues

• Flowise affected by Server-Side Request Forgery (SSRF) in HTTP Node Leading to Internal Network Access - CVE-2026-31829
• jsPDF Affected by Client-Side/Server-Side Denial of Service via Malicious GIF Dimensions - CVE-2026-25535
• HAX open-apis: Credential Theft via Server-Side Request Forgery (SSRF) in open-apis - CVE-2026-46391
• @better-auth/sso provider registration has server-side request forgery via unvalidated OIDC endpoints - CVE-2026-53513

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Tags:

npm

langsmith