# CVE-2025-68665: LangChain serialization injection vulnerability enables secret extraction

> CVE-2025-68665: LangChain serialization injection vulnerability enables secret extraction. CVSS 8.6 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2025-68665
Last updated: 2026-10-19T22:10:00Z

- Published: 2025-12-23 22:56 UTC · Updated: 2026-10-19 22:10 UTC · Assigner: GitHub\_M
- CVSS: 8.6 (CVSS 3.1) · Severity: High · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
- EPSS: 0.79%, 56th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-502

## Description

LangChain is a framework for building LLM-powered applications. Prior to @langchain/core versions 0.3.80 and 1.1.8, and prior to langchain versions 0.3.37 and 1.2.3, a serialization injection vulnerability exists in LangChain JS's toJSON() method (and subsequently when string-ifying objects using JSON.stringify(). The method did not escape objects with 'lc' keys when serializing free-form data in kwargs. The 'lc' key is used internally by LangChain to mark serialized objects. When user-controlled data contains this key structure, it is treated as a legitimate LangChain object during deserialization rather than plain user data. This issue has been patched in @langchain/core versions 0.3.80 and 1.1.8, and langchain versions 0.3.37 and 1.2.3

## Affected vendors and products

- langchain-ai: langchainjs

## Tracked companies

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

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2025-68665)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2025-68665)
- [https://github.com/langchain-ai/langchainjs/commit/e5063f9c6e9989ea067dfdff39262b9e7b6aba62](https://github.com/langchain-ai/langchainjs/commit/e5063f9c6e9989ea067dfdff39262b9e7b6aba62)
- [https://github.com/langchain-ai/langchainjs/releases/tag/%40langchain%2Fcore%401.1.8](https://github.com/langchain-ai/langchainjs/releases/tag/%2540langchain%252Fcore%25401.1.8)
- [https://github.com/langchain-ai/langchainjs/releases/tag/langchain%401.2.3](https://github.com/langchain-ai/langchainjs/releases/tag/langchain%25401.2.3)
- [https://github.com/langchain-ai/langchainjs/security/advisories/GHSA-r399-636x-v7f6](https://github.com/langchain-ai/langchainjs/security/advisories/GHSA-r399-636x-v7f6)

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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-2025-68665 · Markdown: https://rewindex.com/cve/CVE-2025-68665.md · JSON: https://rewindex.com/api/v1/cves/CVE-2025-68665 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T03:11:39.617Z