# CVE-2026-92359: ag-ui-protocol ag-ui permissive CORS policy in CORSMiddleware

Source: https://junglewise.ai/threats/cve-2026-92359-ag-ui-protocol-ag-ui-permissive-cors-policy-in-corsmiddleware  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-16. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-92359 · Severity: low · CVSS 3.1 · Published 2026-09-16

ag-ui is a framework for integrating AI agents into frontend applications. The vulnerability allows attackers to bypass cross-origin security restrictions through a misconfigured CORS (Cross-Origin Resource Sharing) middleware, potentially enabling attackers to make unauthorized requests to ag-ui endpoints from untrusted domains. This could lead to unauthorized access to agent functionality or data exposure if the application relies on browser-based CORS enforcement for security.

Technologies: [Ag-Ui-Protocol Ag-Ui](https://junglewise.ai/threats/technologies/ag-ui). Vendors: [Ag-Ui-Protocol](https://junglewise.ai/threats/vendors/ag-ui-protocol).

## Quick answers

**Is CVE-2026-92359 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-92359 being exploited in the wild.

**How severe is CVE-2026-92359?** Low severity, with a CVSS score of 3.1, published 16 September 2026.

**Which products and versions are affected?** Ag-Ui-Protocol Ag-Ui 0.3.0.

**Is there a fix for CVE-2026-92359?** A patch was published on 2026-08-25: Fix commit 9b143b9668fa52c2054ede9d34a45ac4b4401089 merged Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-92359 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-92359?** Check whether you run Ag-Ui-Protocol Ag-Ui 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.

## Technical details

The vulnerability is a permissive CORS policy misconfiguration in the CORSMiddleware component affecting the create_strands_app function in integrations/aws-strands/python/src/ag_ui_strands/utils.py. The middleware accepts requests from untrusted domains by not properly validating the origin header, allowing cross-domain requests that should have been blocked. The attack is network-accessible and can be launched remotely, though exploitation requires high complexity due to application-specific constraints. The vulnerability is fixed in version AGUI.Abstractions@0.0.6 (commit 9b143b9668fa52c2054ede9d34a45ac4b4401089), which adds an optional authentication hook parameter (auth=None) to provide proper request validation before processing.

## Affected products

- ag-ui-protocol ag-ui 0.3.0

## Timeline

- 2026-09-16: disclosed
- 2026-08-25: patched: Fix commit 9b143b9668fa52c2054ede9d34a45ac4b4401089 merged

## References

- [https://github.com/ag-ui-protocol/ag-ui/](https://github.com/ag-ui-protocol/ag-ui/)
- [https://github.com/ag-ui-protocol/ag-ui/commit/9b143b9668fa52c2054ede9d34a45ac4b4401089](https://github.com/ag-ui-protocol/ag-ui/commit/9b143b9668fa52c2054ede9d34a45ac4b4401089)

## Related threats

- [ag-ui-protocol ag-ui resource exhaustion in interrupt expiry](https://junglewise.ai/threats/cve-2026-120237-a-flaw-has-been-found-in-ag-ui-protocol-ag-ui-up-to-0-0-58)
- [ag-ui Transport Decoder Handler improper input validation](https://junglewise.ai/threats/cve-2026-120236-a-vulnerability-was-detected-in-ag-ui-protocol-ag-ui-up-to-0-0)
- [ag-ui SSE parser resource exhaustion](https://junglewise.ai/threats/cve-2026-120235-a-security-vulnerability-has-been-detected-in-ag-ui-protocol-ag)
- [ag-ui HTTP Transport unbounded response buffering](https://junglewise.ai/threats/cve-2026-120234-a-weakness-has-been-identified-in-ag-ui-protocol-ag-ui-up-to-0-0)
- [ag-ui HttpAgent credential and request body forwarding via redirect](https://junglewise.ai/threats/cve-2026-120233-a-security-flaw-has-been-discovered-in-ag-ui-protocol-ag-ui-up)