CVE-2025-68664

Published Dec 23, 2025

Last updated 4 months ago

Overview

AI description

Automated description summarized from trusted sources.

CVE-2025-68664 is a serialization injection vulnerability found in LangChain, a framework used for building agents and LLM-powered applications. The vulnerability exists in versions prior to 0.3.81 and 1.2.5, specifically within the `dumps()` and `dumpd()` functions. These functions fail to properly escape dictionaries containing the `'lc'` key during serialization. The `'lc'` key is used internally by LangChain to identify serialized objects. When user-controlled data includes this key structure, the system incorrectly interprets it as a legitimate LangChain object during deserialization, rather than treating it as plain user data. This can allow attackers to exfiltrate sensitive environment variables and potentially execute code. The vulnerability has been addressed in versions 0.3.81 and 1.2.5.

Description: LangChain is a framework for building agents and LLM-powered applications. Prior to versions 0.3.81 and 1.2.5, a serialization injection vulnerability exists in LangChain's dumps() and dumpd() functions. The functions do not escape dictionaries with 'lc' keys when serializing free-form dictionaries. 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 versions 0.3.81 and 1.2.5.
Source: security-advisories@github.com
NVD status: Analyzed
Products: langchain_core

Risk scores

CVSS 3.1

Type: Primary
Base score: 8.2
Impact score: 4.2
Exploitability score: 3.9
Vector string: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
Severity: HIGH

Weaknesses

security-advisories@github.com: CWE-502

Hype score: Not currently trending

Configurations

[
  {
    "nodes": [
      {
        "cpeMatch": [
          {
            "criteria": "cpe:2.3:a:langchain:langchain_core:*:*:*:*:*:python:*:*",
            "matchCriteriaId": "DC184324-6CF1-4F7A-B87F-6DD2120C3B3B",
            "versionEndExcluding": "0.3.81",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:a:langchain:langchain_core:*:*:*:*:*:python:*:*",
            "matchCriteriaId": "4298E953-ED96-49EC-8474-86095D560F2B",
            "versionEndExcluding": "1.2.5",
            "versionStartIncluding": "1.0.0",
            "vulnerable": true
          }
        ],
        "negate": false,
        "operator": "OR"
      }
    ]
  }
]

References

Sources include official advisories and independent security research.