{"cve":"CVE-2026-55236","nvd":{"published":"2026-09-14T16:17:12.663","modified":"2026-09-30T19:57:08.043","status":"Deferred","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:N","score":5.9},"cwes":["CWE-285"],"references":["https://github.com/langchain-ai/docs/blob/7b70fbacab21f84d9c6f9848f86cdeb471adbb50/src/langsmith/agent-server-changelog.mdx","https://github.com/langchain-ai/helm/security/advisories/GHSA-jfj5-wrj9-63x4"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:53:43.293028046+00:00"},"epss":{"cve":"CVE-2026-55236","score":0.00255,"percentile":0.16968,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-jfj5-wrj9-63x4","url":"https://osv.dev/vulnerability/GHSA-jfj5-wrj9-63x4","summary":"langgraph-api: Incomplete assistant authorization in LangGraph Server run creation","modified":"2026-09-10T12:26:07.991154905Z","packages":[{"ecosystem":"PyPI","name":"langgraph-api","purl":"pkg:pypi/langgraph-api","ranges":["<0.10.0"],"fixed":["0.10.0"]}]},{"id":"PYSEC-2026-3858","url":"https://osv.dev/vulnerability/PYSEC-2026-3858","summary":"langgraph-api: Incomplete assistant authorization in LangGraph Server run creation","modified":"2026-09-10T12:15:08.178882304Z","packages":[{"ecosystem":"PyPI","name":"langgraph-api","purl":"pkg:pypi/langgraph-api","ranges":["<0.10.0"],"fixed":["0.10.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}