Independent & educational platform Not a government body. No link or affiliation with any government organisation. Made for learning only. Test only systems you own or are authorised to test. Become a Partner or Sponsor → Full disclaimer

CVE-2025-68665

critical

LangChain is a framework for building LLM-powered applications.

Vendor / product: Langchain — langchain.js

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
9.1
9.1 (CVSS v3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Severity source: NVD CVSS v3.1 (nvd@nist.gov)
Timeline (UTC)
Published: 2025-12-23 23:15
Modified: 2026-10-19 22:10
NVD status: Analyzed
Last synced 2 days ago
Verified against the source API 2026-10-27 07:07 UTC
Exploitation
Not listed in CISA KEV (as of last catalog sync)
Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).

Affected products

langchain / langchain.js <0.3.37, ≥1.0.0 <1.2.3
langchain / langchain\/core <0.3.80, ≥1.0.0 <1.1.8

Weakness classification (CWE)

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

Vendor advisory: https://github.com/langchain-ai/langchainjs/security/advisories/GHSA-r399-636x-v7f6
Vendor advisory: https://github.com/langchain-ai/langchainjs/security/advisories/GHSA-r399-636x-v7f6
Patch / mitigation: https://github.com/langchain-ai/langchainjs/commit/e5063f9c6e9989ea067dfdff39262b9e7b6aba62

References

Data sources

NVD CVE API 2.0 — fetched 2026-10-27 07:07 UTC · record ↗

Learn the basics

Understanding CVEs and CVSS Scores

Related CVEs