# Windows ML CLI: CORS misconfig enables localhost RCE

Advisory record · `GHSA-96p9-rh4f-92cf`

- **Identifiers:** `GHSA-96p9-rh4f-92cf` · `CVE-2026-84452` · `PYSEC-2026-3944`
- **State:** Confirmed
- **Severity:** CVSS 8.6 High
- **Critical:** No
- **Weakness (CWE):** [CWE-306](https://cwe.mitre.org/data/definitions/306.html) · [CWE-942](https://cwe.mitre.org/data/definitions/942.html)
- **Tags:** [Authentication bypass](https://agentprime.io/advisories/tag/auth-bypass.md) · [CWE-942](https://agentprime.io/advisories/tag/cwe-942.md)
- **Published:** 8 Sept 2026
- **Updated:** 10 Sept 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 8 Sept 2026, 21:27 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `winml-cli` (PyPI): affected `<0.4.0`; fixed in `0.4.0`

## Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

> GHSA-96p9-rh4f-92cf affects the winml-cli Python package versions before 0.4.0, fixed in 0.4.0. Its HTTP API sets a wildcard CORS origin on a server bound to localhost, and the build and config commands accept a trust_remote_code flag. A malicious website visited by a user running the server could trigger execution of code from an attacker-controlled model repository, giving code execution as the server user. Upgrade to winml-cli 0.4.0 or later.

Written 1 Nov 2026.

## Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

## Severity and exploitation

- 8.6 High, CVSS 4.0: `CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`, from CNA (GitHub_M)

- **CISA KEV:** Not listed.
- **EPSS:** 0.016, the 76th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 31 Oct 2026, 14:10 UTC: First seen by agentprime
- 31 Oct 2026, 14:10 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-96p9-rh4f-92cf)

## Sources

- [GitHub Advisory Database: GHSA-96p9-rh4f-92cf](https://github.com/advisories/GHSA-96p9-rh4f-92cf)
- [OSV: GHSA-96p9-rh4f-92cf](https://osv.dev/vulnerability/GHSA-96p9-rh4f-92cf)
- <https://github.com/microsoft/winml-cli/security/advisories/GHSA-96p9-rh4f-92cf>
- <https://nvd.nist.gov/vuln/detail/CVE-2026-84452>
- <https://github.com/microsoft/winml-cli/pull/1321>
- <https://github.com/microsoft/winml-cli/commit/f4073e0ef4700a25b623487e7e45c421ca0b9993>
- <https://github.com/microsoft/winml-cli>

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.

## Check whether this affects you

A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: <https://agentprime.io/mcp.md>
- In a browser: <https://agentprime.io/check/> reads your lockfile in the browser, never uploading it.
- Whether it touches your code, with file and line: the Claude Code plugin, <https://agentprime.io/plugin.md>
- As JSON: <https://api.agentprime.io/v1/advisories/GHSA-96p9-rh4f-92cf>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

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The web page: <https://agentprime.io/advisories/GHSA-96p9-rh4f-92cf/>. Everything for agents: <https://agentprime.io/llms.txt>.