# CERT-FR Advisory: CPython Data Integrity Flaw

Published: 2026-09-30 · Severity: routine
Canonical: https://vorant.io/reports/4a8d50d9-4968-5bbe-9e60-8bbcf9942c4c/cert-fr-advisory-cpython-data-integrity-flaw

> A CPython vulnerability (CVE-2026-12345) allows an attacker to compromise data integrity; patch to the latest secure version.

CERT-FR has issued an advisory regarding a vulnerability in CPython, the reference implementation of the Python programming language. The flaw, tracked as CVE-2026-12345 and detailed in Python Security Response Team advisory PSF-2026-42, allows an attacker to cause a data integrity compromise on affected systems. Systems running CPython without the latest security patch are affected.

No evidence of active exploitation is mentioned in the bulletin. CERT-FR recommends organizations consult the official Python security bulletin for patch details and apply the update promptly. This is a routine vendor patch advisory rather than a report of in-the-wild attack activity.

## Mentioned in this report

- Vulnerabilities: CVE-2026-12345

Source reporting: https://www.cert.ssi.gouv.fr/avis/CERTFR-2026-AVI-1239

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