# CPython CVE-2026-9669 enables remote DoS

Published: 2026-06-09 · Severity: high
Canonical: https://vorant.io/reports/89529bc1-1469-43b2-9894-ddf0dda9f463/cpython-cve-2026-9669-enables-remote-dos

> A vulnerability in CPython allows attackers to trigger remote denial of service against unpatched systems.

The French national cybersecurity agency ANSSI has published an advisory warning of a denial-of-service vulnerability in CPython, tracked as CVE-2026-9669. The flaw affects CPython installations that have not applied the latest security patch.

The vulnerability permits remote attackers to cause a denial-of-service condition without requiring authentication or user interaction. The Python Software Foundation released security patches on June 8, 2026, addressing this issue across supported versions.

Organisations running Python-based applications and services should prioritise patching to mitigate the risk of service disruption. The advisory recommends consulting the official Python security bulletin for patch availability and deployment guidance.

## Mentioned in this report

- Vulnerabilities: CVE-2026-9669

Source reporting: https://www.cert.ssi.gouv.fr/avis/CERTFR-2026-AVI-0704

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