CVE-2025-686658.6HighCWE-502

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

langchain-ai · langchainjs

Affected: langchain-ai langchainjs · Exploitation: unlikely (under 1%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

0.8%probability of exploitation in the next 30 days

56th percentile

050100

Higher than 56% of scored CVEs

8.6HighCVSS 3.1

LowMediumHighCrit.

DescriptionCVE.org

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 products1

From the CVE record. A product or version that is not listed is unknown, not unaffected.

langchain-ai · langchainjs@langchain/core >= 1.0.0, < 1.1.8; @langchain/core < 0.3.80; langchain >= 1.0.0, < 1.2.3; langchain < 0.3.37

On the Atlas

Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.

Open the Atlas

Exploitation: Unlikely (under 1%). EPSS under 1%, or no score yet.
CISA KEV: Not listed
Public check: No public nuclei template
Weakness: Deserialization of Untrusted Data · Deserialization and Object Injection
Vendor: langchain-ai
Published: December 2025
Band: Unlikely (under 1%), December 2025

CoverageNo articles yet

No CyberSIXT article names CVE-2025-68665 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.