AI and data stack advisories

Severe, 6 weeks1496Projects326

1496 severe, 6 weeks · 326 projects

JupyterPYSEC-2026-3472

Jupyter: code execution

Jupyter

CVE-2026-6657 · Published Jul 23, 2026

Medium6.1
No fix yet
Source advisory

A vulnerability in jupyter-server versions 1.12.0 through 2.17.0 allows an attacker to bypass CORS origin validation when the allow_origin_pat configuration is used. The issue arises from the use of re.match() for validating the Origin header, which only anchors at the start of the string. This allows attacker-controlled domains such as trusted.example.com.evil.com to pass validation against patterns intended to match trusted.example.com. The vulnerability affects multiple locations in the codebase, including CORS headers, WebSocket connections, referer validation, and login redirects, potentially enabling phishing attacks, arbitrary code execution, and unauthorized access to sensitive API responses.

Affected versions

PackageAffectedFixed in
jupyter-server
PyPI
>= 1.12.0, <= 2.17.0No fix yet
Details and references

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