What’s Vulnerable › Vulnerabilities

CVE-2026-84452: Windows ML CLI: CORS misconfig enables localhost RCE

• Severity: high (CVSS 8.6 v4.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.6% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-09-02 · updated 2026-09-28
• Weakness: CWE-306

Description

Windows ML CLI is a command line tool for building portable, performant, and high-quality AI models for Windows ML. Prior to 0.4.0, the src/winml/modelkit/serve/cli_api.py component exposes WinML CLI commands through a localhost HTTP API without authentication and configures the allow_origins setting as a wildcard in both src/winml/modelkit/serve/cli_api.py and src/winml/modelkit/serve/app.py. A malicious website loaded by a user can send cross-origin requests to /v1/cli/build or /v1/cli/config and set the trust_remote_code parameter to true, which is converted to the --trust-remote-code command-line flag without validation. This reaches AutoConfig.from_pretrained with trust_remote_code=True in src/winml/modelkit/loader/_autoconfig.py and imports Python code from an attacker-controlled model repository, resulting in arbitrary code execution as the server user. This issue is fixed in version 0.4.0.

Affected products

• microsoft winml-cli: before 0.4.0

References

• https://github.com/microsoft/winml-cli/commit/f4073e0ef4700a25b623487e7e45c421ca0b9993
• https://github.com/microsoft/winml-cli/pull/1321
• https://github.com/microsoft/winml-cli/security/advisories/GHSA-96p9-rh4f-92cf
• https://github.com/microsoft/winml-cli/security/advisories/GHSA-96p9-rh4f-92cf

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