# LangGraph Checkpoint affected by RCE in "json" mode of JsonPlusSerializer

Advisory record · `GHSA-wwqv-p2pp-99h5`

- **Identifiers:** `GHSA-wwqv-p2pp-99h5` · `CVE-2025-64439` · `PYSEC-2026-1527`
- **State:** Confirmed
- **Severity:** CVSS 7.4 High
- **Critical:** No
- **Weakness (CWE):** [CWE-502](https://cwe.mitre.org/data/definitions/502.html)
- **Tags:** [Insecure deserialization](https://agentprime.io/advisories/tag/deserialization.md)
- **Published:** 5 Nov 2025
- **Updated:** 7 Jul 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 5 Nov 2025, 19:52 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `langgraph-checkpoint` (PyPI): affected `<3.0.0`; fixed in `3.0.0`

## Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

## Severity and exploitation

- 7.4 High, CVSS 4.0: `CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:H/SC:H/SI:H/SA:H`, from CNA (GitHub_M)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0089, the 59th percentile, on 13 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

This record came from the full history of the GitHub Advisory Database, published 5 Nov 2025. New records show when each source confirmed them.

## Sources

- [GitHub Advisory Database: GHSA-wwqv-p2pp-99h5](https://github.com/advisories/GHSA-wwqv-p2pp-99h5)
- [OSV: GHSA-wwqv-p2pp-99h5](https://osv.dev/vulnerability/GHSA-wwqv-p2pp-99h5)
- <https://github.com/langchain-ai/langgraph/security/advisories/GHSA-wwqv-p2pp-99h5>
- <https://nvd.nist.gov/vuln/detail/CVE-2025-64439>
- <https://github.com/langchain-ai/langgraph/commit/c5744f583b11745cd406f3059903e17bbcdcc8ac>
- <https://github.com/langchain-ai/langgraph>
- <https://github.com/langchain-ai/langgraph/blob/c5744f583b11745cd406f3059903e17bbcdcc8ac/libs/checkpoint/langgraph/checkpoint/serde/jsonplus.py>
- <https://github.com/langchain-ai/langgraph/releases/tag/checkpoint%3D%3D3.0.0>

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.

## Check whether this affects you

A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: <https://agentprime.io/mcp.md>
- In a browser: <https://agentprime.io/check/> reads your lockfile in the browser, never uploading it.
- Whether it touches your code, with file and line: the Claude Code plugin, <https://agentprime.io/plugin.md>
- As JSON: <https://api.agentprime.io/v1/advisories/GHSA-wwqv-p2pp-99h5>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

---

The web page: <https://agentprime.io/advisories/GHSA-wwqv-p2pp-99h5/>. Everything for agents: <https://agentprime.io/llms.txt>.