CVE-2025-68665: langchain-ai langchainjs Deserialization of Untrusted Data
Vulnerability summary
CVE-2025-68665 is a critical (CVSS 9.1) Deserialization of Untrusted Data vulnerability in langchain-ai langchainjs. EPSS estimates a 0.79% chance of exploitation in the next 30 days, higher than 55.5% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 0 · Related 3Timeline
- 23-12-2025PublishedVulnerability first disclosed.
- 24-12-2025Last modifiedVulnerability information updated.
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
CVSS metrics
4 scores · 4 sources · 1 version- CVE.orgCNA8.6HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:NDiffers
- OSV · NpmEcosystem advisory · calculated8.6HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:NDiffers
- OSV · ChainguardEcosystem advisory · calculated8.6HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:NDiffers
EPSS trend
Probability
0.79%
Chance of exploitation in the next 30 days
Percentile
56%
Versus all other CVEs
30-day change
0.00 pp
From 0.79% on 19-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Chainguard25 products
- kibana-8.17< 8.17.10-r6
- kibana-8.17-bitnami< 8.17.10-r6
- kibana-8.17-iamguarded< 8.17.10-r6
- kibana-8.18< 8.18.8-r6
- kibana-8.18-bitnami< 8.18.8-r6
Langchain2 products
- langchain\/core< 0.3.80 | ≥ 1.0.0, < 1.1.8
- langchain.js< 0.3.37 | ≥ 1.0.0, < 1.2.3
@langchain1 product
- core≥ 1.0.0, < 1.1.8 | < 0.3.80
Langchain-ai1 product
- 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
Npm1 product
- langchain≥ 1.0.0, < 1.2.3 | < 0.3.37
5 vendors · 30 products
References
7 links- github.com/langchain-ai/langchainjs/security/advisories/GHSA-r399-636x-v7f6X Refsource CONFIRMWEBAdvisoryVendor Advisory
- github.com/langchain-ai/langchainjs/commit/e5063f9c6e9989ea067dfdff39262b9e7b6aba62X Refsource MISCWEBFIXPatch
- github.com/langchain-ai/langchainjs/releases/tag/%40langchain%2Fcore%401.1.8X Refsource MISCWEBRelease Notes
