LangChain serialization injection vulnerability enables secret extraction (GHSA-r399-636x-v7f6)

Description

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.

Recommendation

Update the @langchain/core package to the latest compatible version. Followings are version details:

• Affected version(s): **< 0.3.80

  >= 1.0.0, < 1.1.8**

• Patched version(s): **0.3.80

  1.1.8**

References

• GHSA-r399-636x-v7f6
• CVE-2025-68665
• CWE-502
• CAPEC-310
• OWASP 2021-A6
• OWASP 2021-A8

Related Issues

• LangChain serialization injection vulnerability enables secret extraction - CVE-2025-68665
• FUXA SQL Injection vulnerability (GHSA-p46g-8c3q-89p2) - CVE-2023-31719
• systeminformation has a Command Injection vulnerability in fsSize() function on Windows - CVE-2025-68154
• Lodash has Prototype Pollution Vulnerability in `_.unset` and `_.omit` functions (GHSA-xxjr-mmjv-4gpg) 2 - CVE-2025-13465

Tags:

npm

@langchain/core