# CVE-2026-118668: LangGraph JavaScript custom authentication may permit cross-user Store access

> CVE-2026-118668: LangGraph JavaScript custom authentication may permit cross-user Store access. CVSS 8.6 (CVSS 4.0).

Canonical: https://rewindex.com/cve/CVE-2026-118668
Last updated: 2026-10-29T18:17:28Z

- Published: 2026-10-28 21:06 UTC · Updated: 2026-10-29 18:17 UTC · Assigner: GitHub\_M
- CVSS: 8.6 (CVSS 4.0) · Severity: High
- EPSS: 0.37%, 31th percentile (scored 2026-11-04)
- CISA KEV: no
- CWE: CWE-639, CWE-863

## Description

langgraph-api implements the LangGraph API for rapid development and testing. From 0.1.2 until 0.15.0, JavaScript or TypeScript custom authentication Store authorization handlers can return a rewritten namespace that is not carried across the runtime boundary and applied before the Store operation. An authenticated user can therefore access another user's Store namespace when a deployment relies on namespace rewriting for isolation, allowing unauthorized reads, overwrites, searches, or deletions. Python custom authentication and handlers that reject unauthorized namespaces instead of rewriting them are not affected. This issue is fixed in version 0.15.0.

## Affected vendors and products

- langchain-ai: langgraph-api

## Tracked companies

- [LangChain (LangSmith)](https://rewindex.com/company/langchain-langsmith.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-118668)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-118668)
- [https://github.com/langchain-ai/langgraph/security/advisories/GHSA-4hm6-w6qq-w73v](https://github.com/langchain-ai/langgraph/security/advisories/GHSA-4hm6-w6qq-w73v)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-118668 · Markdown: https://rewindex.com/cve/CVE-2026-118668.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-118668 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-11-05T14:06:30.957Z