Deserialization of Untrusted Data Affecting py3-langchain package, versions <1.2.6-r0


Severity

Recommended
0.0
high
0
10

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Threat Intelligence

Exploit Maturity
Proof of Concept
EPSS
43.42% (99th percentile)

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  • Snyk IDSNYK-WOLFILATEST-PY3LANGCHAIN-15411697
  • published5 Mar 2026
  • disclosed23 Dec 2025

Introduced: 23 Dec 2025

CVE-2025-68664  (opens in a new tab)
CWE-502  (opens in a new tab)

How to fix?

Upgrade Wolfi py3-langchain to version 1.2.6-r0 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream py3-langchain package and not the py3-langchain package as distributed by Wolfi. See How to fix? for Wolfi relevant fixed versions and status.

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.

CVSS Base Scores

version 3.1