CERT-FR Flags CPython Security Bypass Flaw
CERT-FR advises patching CPython to fix a flaw allowing attackers to bypass security policy, tracked as CVE-2026-103995.
Sourcecert.cyber.gouv.fr — open the original
What to check
- Applies to
- The 1 CVE named below. Whether you run an affected version is not assessed: check the versions the source lists.
- Exploitation
- No exploitation in the wild and no public exploit is recorded for the CVEs named.
CERT-FR has published an advisory regarding a vulnerability in CPython, the reference implementation of the Python programming language. The flaw, identified as CVE-2026-103995 and documented in Python Software Foundation advisory PSF-2026-47, allows an attacker to bypass security policy controls. The advisory does not specify technical details of the exploitation mechanism, affected version ranges, or whether the vulnerability is being actively exploited in the wild.
Affected systems are any CPython installations that have not applied the latest security patch referenced in the PSF advisory. Defenders should consult the official Python Software Foundation advisory and apply the corresponding patch to remediate the issue. Given the lack of detail on exploitation complexity or active exploitation, and the nature of the impact being a security policy bypass rather than remote code execution or privilege escalation, this should be treated as a routine patching action.
Mentioned in this report
Source reporting: https://www.cert.cyber.gouv.fr/avis/CERTFR-2026-AVI-1397
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