CVE-2025-64439: langchain-ai langgraph Deserialization of Untrusted Data

Vulnerability summary

CVE-2025-64439 is a high (CVSS 7.4) Deserialization of Untrusted Data vulnerability in langchain-ai langgraph. EPSS estimates a 0.89% chance of exploitation in the next 30 days, higher than 58.6% of scored vulnerabilities.

Timeline

1. 07-11-2025
   PublishedVulnerability first disclosed.
2. 07-11-2025
   Last modifiedVulnerability information updated.

Description

LangGraph SQLite Checkpoint is an implementation of LangGraph CheckpointSaver that uses SQLite DB (both sync and async, via aiosqlite). In versions 2.1.2 and below, the JsonPlusSerializer (used as the default serialization protocol for all checkpointing) contains a Remote Code Execution (RCE) vulnerability when deserializing payloads saved in the "json" serialization mode. By default, the serializer attempts to use "msgpack" for serialization. However, prior to version 3.0 of the checkpointer library, if illegal Unicode surrogate values caused serialization to fail, it would fall back to using the "json" mode. This issue is fixed in version 3.0.0.

• CWE-502Deserialization of Untrusted DataThe product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.