High 8.6Published Dec 23, 2025

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

Updated under an hour ago (Oct 26, 2026, 7:40 PM ET)

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It affects langchain-ai langchainjs and 2 other products. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for langchain-ai langchainjs

Exploited in the last 30 days

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

CVSS: 8.6 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
Weakness (CWE): CWE-502
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Dec 24, 2025
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

langchain-ai langchainjs langchain_ai:langchainjs (from the name)	@langchain/core >= 1.0.0, < 1.1.8; @langchain/core < 0.3.80; langchain >= 1.0.0, < 1.2.3; langchain < 0.3.37	CNA record
langchain langchain.js langchain:langchain.js	before 0.3.37; from 1.0.0 before 1.2.3	NVD
langchain langchain/core langchain:langchain/core	before 0.3.80; from 1.0.0 before 1.1.8	NVD

References

References

https://github.com/langchain-ai/langchainjs/security/advisories/GHSA-r399-636x-v7f6	x-refsource-confirm, vendor-advisory
https://github.com/langchain-ai/langchainjs/commit/e5063f9c6e9989ea067dfdff39262b9e7b6aba62	x-refsource-misc, patch
https://github.com/langchain-ai/langchainjs/releases/tag/%40langchain%2Fcore%401.1.8	x-refsource-misc, release-notes
https://github.com/langchain-ai/langchainjs/releases/tag/langchain%401.2.3	x-refsource-misc, release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.