Is CVE-2026-55236 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-55236 being exploited in the wild.

How severe is CVE-2026-55236?

Medium severity, with a CVSS score of 5.9, published 14 September 2026.

Which products and versions are affected?

langgraph-api (PyPI) < 0.10.0, ECOSYSTEM:introduced=0,fixed=0.10.0.

Is there a fix for CVE-2026-55236?

Yes. langgraph-api (PyPI): upgrade to 0.10.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-55236 attacked?

It is attacked over the network, in a hosted service.

Am I affected by CVE-2026-55236?

Check whether you run langgraph-api (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-55236: LangChain langgraph-api authorization bypass in run creation

Q: Is there a fix for CVE-2026-55236?

Yes. langgraph-api (PyPI): upgrade to 0.10.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-55236 attacked?

It is attacked over the network, in a hosted service.

Q: Am I affected by CVE-2026-55236?

Check whether you run langgraph-api (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-55236 · Severity: medium · CVSS 5.9 · Published 2026-09-14

LangGraph Server is a runtime platform for deploying AI agent workflows. In affected versions, the run creation endpoint failed to properly authorize which assistants (AI configurations) a user could access, allowing an authenticated user to create workflow runs using private assistants owned by other users. The response would expose the private assistant's sensitive metadata, configuration, and context—which may include API keys, credentials, or system prompts—creating both data exposure and unauthorized workflow execution risks.

Technologies: langgraph-api (PyPI). Vendors: PyPI.

Quick answers

Is CVE-2026-55236 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-55236 being exploited in the wild.
How severe is CVE-2026-55236?: Medium severity, with a CVSS score of 5.9, published 14 September 2026.
Which products and versions are affected?: langgraph-api (PyPI) < 0.10.0, ECOSYSTEM:introduced=0,fixed=0.10.0.
Is there a fix for CVE-2026-55236?: Yes. langgraph-api (PyPI): upgrade to 0.10.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-55236 attacked?: It is attacked over the network, in a hosted service.
Am I affected by CVE-2026-55236?: Check whether you run langgraph-api (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

langgraph-api (PyPI): upgrade to 0.10.0 or later
```
pip install "langgraph-api>=0.10.0"
```

Technical details

The vulnerability stems from incomplete authorization logic (CWE-285) in the run-creation code path. While assistant reads and cron creation dispatch the assistants.read authorization event, run creation dispatched assistants.search with incomplete parameters. In deployments with custom authorization handlers registering only an assistants.read handler (without a global fallback), the run-creation path skipped authorization entirely, omitting the owner constraint from database queries. An authenticated attacker could POST to the run-creation endpoint referencing another user's private assistant by ID; the server would execute the run and return the referenced assistant's metadata, config, and context in the response. Attack requires low privileges (authenticated user account) and network reachability to the LangGraph API. No user interaction needed. Fixed in langgraph-api 0.10.0 by aligning run/cron creation to use the assistants.read event consistently with other code paths.

Affected products

LangChain langgraph-api < 0.10.0

Identifiers

CVE-2026-55236
GHSA-jfj5-wrj9-63x4
PYSEC-2026-3858

Timeline

2026-06-11: disclosed
2026-08-19: advisory: GitHub Advisory Database publication
2026-08-19: patched: Fixed in langgraph-api 0.10.0

References

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