---
id: CVE-2026-55236
title: langgraph-api implements the LangGraph API for rapid development and testing
summary: >-
  langgraph-api implements the LangGraph API for rapid development and testing.
  Prior to 0.10.0, the langgraph-api run-creation path authorizes the assistant
  attached to a run by dispatching assistants.search with an incomplete value
  inste…
severity: medium
cvss: 5.9
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:N'
cwe:
  - CWE-285
vendor: langchain-ai
product: langgraph-api
affected:
  - langgraph-api < 0.10.0
patched:
  - langgraph-api 0.10.0
published: '2026-09-14'
updated: '2026-09-14'
sourceUpdated: '2026-09-14T17:17:48.093'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-55236'
references:
  - url: >-
      https://github.com/langchain-ai/docs/blob/7b70fbacab21f84d9c6f9848f86cdeb471adbb50/src/langsmith/agent-server-changelog.mdx
    label: security-advisories@github.com
  - url: >-
      https://github.com/langchain-ai/helm/security/advisories/GHSA-jfj5-wrj9-63x4
    label: security-advisories@github.com
  - url: 'https://github.com/langchain-ai/helm'
  - url: 'https://pypi.org/project/langgraph-api'
  - url: 'https://github.com/advisories/GHSA-jfj5-wrj9-63x4'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-55236'
tags:
  - nvd
  - cve.org
  - osv
  - pip
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-14T16:41:45.325753Z'
aliases:
  - GHSA-jfj5-wrj9-63x4
  - PYSEC-2026-3858
ecosystem: pip
ingestedAt: '2026-08-19T19:22:19.360Z'
epss: 0.0016
epssPercentile: 0.05588
---

## Overview

langgraph-api implements the LangGraph API for rapid development and testing. Prior to 0.10.0, the langgraph-api run-creation path authorizes the assistant attached to a run by dispatching assistants.search with an incomplete value instead of the assistants.read event used by direct reads and cron creation. In deployments with custom resource handlers that register only assistants.read, omit an assistants.search handler, and have no global fallback handler, no applicable handler supplies an owner filter, allowing a low-privileged user to reference another user's private assistant through POST /runs or POST /threads/{thread_id}/runs. The run-creation response can disclose the private assistant's metadata, config, and context, and the run can execute using that assistant's configuration. Deployments without custom authorization handlers, or with an equivalent owner filter applied through a global handler or across all assistant events, are not affected. This issue is fixed in version 0.10.0.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Package advisory (CVE-2026-55236)

Affected packages:

- `langgraph-api < 0.10.0`

Patched in:

- `langgraph-api 0.10.0`

Source: https://osv.dev/vulnerability/GHSA-jfj5-wrj9-63x4