Answer in brief
CVE-2026-55236 records a Medium severity (CVSS 5.9) vulnerability in langgraph-api: Incomplete assistant authorization in LangGraph Server run creation. The current sources do not mark it as known exploited. The current feed maps langchain-ai/langgraph-api (generic), langgraph-api (pip), langgraph-api (pypi). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 5.9. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps langchain-ai/langgraph-api (generic), langgraph-api (pip), langgraph-api (pypi). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| langchain-ai/langgraph-apigeneric | < 0.10.0 | Not reported |
| langgraph-apipip | <0.10.0 | 0.10.0 |
| langgraph-apipypi | >=0 <0.10.0 | 0.10.0 |
Published upstream
Sep 14, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 14, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 19, 2026
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.
Quoted source text, attributed separately from HOL analysis.