CVE-2026-55236langgraph-api: Incomplete assistant authorization in LangGraph Server run creation
- 5.9MediumCVSS base score
- 0.26%Exploitation in 30 daysEPSS · top 83% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
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.
Timeline
ID reserved
By GitHub_M
- 3 months later
· 3 months later
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium5.9 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:N |
| NVDNVD · Deferred | 3.1 | Medium5.9 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.26% · top 83% of all CVEs (15 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.9.
Affected products
- affected < 0.10.0
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- PyPIlanggraph-apiGHSA-jfj5-wrj9-63x4 (opens in a new tab)
References
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-77583 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-jfj5-wrj9-63x4 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-55236)Record last updated .