# CVE-2026-92359: ag-ui-protocol ag-ui CORSMiddleware utils.py create_strands_app cross-domain policy

> An attacker can bypass cross-domain restrictions due to permissive CORS policies in the ag-ui-protocol library, potentially enabling unauthorized cross-origin requests.

- **Severity:** Low 2.3 (`CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 16 Sep 2026
- **Updated:** 16 Sep 2026
- **Also known as:** GHSA-fq29-84pr-2m3x

## What is CVE-2026-92359?

CVE-2026-92359 is a low-severity vulnerability in ag-ui-protocol ag-ui, published on 16 Sep 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

A security flaw has been discovered in ag-ui-protocol ag-ui 0.3.0. The affected element is the function create_strands_app of the file integrations/aws-strands/python/src/ag_ui_strands/utils.py of the component CORSMiddleware. The manipulation results in permissive cross-domain policy with untrusted domains. The attack may be launched remotely. The attack requires a high level of complexity. The exploitability is described as difficult. Upgrading to version AGUI.Abstractions@0.0.6 is sufficient to fix this issue. The patch is identified as 9b143b9668fa52c2054ede9d34a45ac4b4401089. It is suggested to upgrade the affected component.

Weakness: CWE-942 (Permissive Cross-domain Security Policy with Untrusted Domains), CWE-346 (Origin Validation Error)

## Which versions are affected by CVE-2026-92359?


## How do I fix CVE-2026-92359?

No fix has been published for CVE-2026-92359 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-92359 being exploited?

There is no known exploitation of CVE-2026-92359 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-92359 and fix it if it is affected.

What it is: CVE-2026-92359 is a low-severity vulnerability in ag-ui-protocol ag-ui, published on 16 Sep 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-92359 in the wild and no public exploit code.

Affected product: ag-ui-protocol ag-ui. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-92359/ (Markdown: https://insights.sbomify.com/CVE-2026-92359/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-92359
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-92359
- OSV: https://osv.dev/vulnerability/CVE-2026-92359

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-92359/
Summaries are generated and may contain mistakes; the official description above is the record.