CVE-2025-68665LangChain serialization injection vulnerability enables secret extraction
- 8.6HighCVSS base score
- 0.79%Exploitation in 30 daysEPSS · top 43% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- YesPublic exploitsa reference or SSVC says so
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
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. A reference of the record is tagged as an exploit. CISA's SSVC rates its exploitation: a proof of concept is public.
Show the exploits1
References tagged exploit1 reference
- https://github.com/langchain-ai/langchainjs/security/advisories/GHSA-r399-636x-v7f6 (opens in a new tab)x_refsource_CONFIRMexploit
Timeline
ID reserved
By GitHub_M
- 1 day later
· 1 day later
Published
- 1 day later
· 1 day later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | High8.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N |
| NVDNVD · Analyzed | 3.1 | Critical9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |
- EPSS (exploitation in 30 days)
- 0.79% · top 43% of all CVEs (15 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.6.
Affected products
- affected @langchain/core >= 1.0.0, < 1.1.8
- affected @langchain/core < 0.3.80
- affected langchain >= 1.0.0, < 1.2.3
- affected langchain < 0.3.37
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- npm@langchain/coreGHSA-r399-636x-v7f6 (opens in a new tab)
- npmlangchainGHSA-r399-636x-v7f6 (opens in a new tab)
References
References4
- https://github.com/langchain-ai/langchainjs/security/advisories/GHSA-r399-636x-v7f6 (opens in a new tab)x_refsource_CONFIRMexploit
- https://github.com/langchain-ai/langchainjs/commit/e5063f9c6e9989ea067dfdff39262b9e7b6aba62 (opens in a new tab)x_refsource_MISC
- https://github.com/langchain-ai/langchainjs/releases/tag/%40langchain%2Fcore%401.1.8 (opens in a new tab)x_refsource_MISC
- https://github.com/langchain-ai/langchainjs/releases/tag/langchain%401.2.3 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2025-204846 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-r399-636x-v7f6 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2025-68665)Record last updated .