> CVE-2026-27448 [LOW]

« BACK_TO_HOME
PUBLISHED
2026-03-18 00:16
MODIFIED
2026-03-18 00:16
CVSS_SCORE V3
1.7
EPSS (Prob. Exploit)
0.41%
Top 66.1%
DATA SOURCES:
NVD 🔗 2026-03-18 RED HAT 🔗 2026-03-22 CWE MITRE 🔗 2026-11-01 FIRST EPSS 🔗 2026-10-25 GITHUB 🔗 2026-11-05 OSV 🔗 2026-09-20 MSRC 🔗 2026-11-02

> DESCRIPTION

pyOpenSSL is a Python wrapper around the OpenSSL library. Starting in version 0.14.0 and prior to version 26.0.0, if a user provided callback to `set_tlsext_servername_callback` raised an unhandled exception, this would result in a connection being accepted. If a user was relying on this callback for any security-sensitive behavior, this could allow bypassing it. Starting in version 26.0.0, unhandled exceptions now result in rejecting the connection.

> AFFECTED_PRODUCTS

ℹ️ Aucun produit affecté n'a encore été publié par NVD pour cette CVE.

> CVSS V3 METRICS

CVSS_VECTOR
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

> MÉTRIQUES CVSS DÉTAILLÉES

CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Métrique Valeur Interprétation
AV (Vecteur d'Attaque)
Attack Vector
Network (N)
Exploit possible à distance via réseau (HTTP, API, etc.)
AC (Complexité d'Attaque)
Attack Complexity
High (H)
Conditions spécifiques doivent être réunies pour exploiter
PR (Privilèges Requis)
Privileges Required
None (N)
Aucune authentification requise
UI (Interaction Utilisateur)
User Interaction
None (N)
Aucune interaction utilisateur nécessaire
S (Périmètre)
Scope
Unchanged (U)
Impact reste dans le périmètre du composant compromis
C (Impact Confidentialité)
Confidentiality Impact
None (N)
Aucune divulgation d'informations
I (Impact Intégrité)
Integrity Impact
Low (L)
Modification limitée des données possible
A (Impact Disponibilité)
Availability Impact
None (N)
Aucune interruption de service

> RÉSUMÉ DES IMPACTS

Confidentialité
None
Aucune divulgation d'informations
Intégrité
Low
Modification limitée des données possible
Disponibilité
None
Aucune interruption de service

> WEAKNESSES

CWE-636

> CWE DETAILED DESCRIPTIONS

CWE-636: Not Failing Securely - When the product encounters an error condition or failure, its design requires it to fall back to a state that is less secure than other options that are available, such as selecting the weakest encryption algorithm or using the most permissive access control restrictions.

> RED HAT SEVERITY ASSESSMENT

THREAT SEVERITY
Moderate

> GITHUB SECURITY ADVISORY

GHSA-vp96-hxj8-p424 LOW

pyOpenSSL allows TLS connection bypass via unhandled callback exception in set_tlsext_servername_callback

AFFECTED PACKAGES:
PIP / pyopenssl
>= 0.14.0, < 26.0.0
Fixed in: 26.0.0

> OSV (GOOGLE OPEN SOURCE VULNERABILITIES)

pyOpenSSL allows TLS connection bypass via unhandled callback exception in set_tlsext_servername_callback

AFFECTED PACKAGES:
Unknown / Unknown
ALIASES:
GHSA-vp96-hxj8-p424, PYSEC-2026-2268

> HISTORIQUE DES MODIFICATIONS

Première apparition
18/03/2026 00:16
Source: NVD
📊 ENRICHISSEMENT 01/11/2026 06:58
CWE
Champ modifié: Description CWE
Ancienne valeur:
CWE-636: Not Failing Securely ('Failing Open') - When the product encounters an error condition or failure, its design requires it to fall back to a state that is less secure than other options that a...
Nouvelle valeur:
CWE-636: Not Failing Securely - When the product encounters an error condition or failure, its design requires it to fall back to a state that is less secure than other options that are available, suc...
📊 ENRICHISSEMENT 01/04/2026 06:02
CWE
Champ modifié: Description CWE
Ancienne valeur:
N/A
Nouvelle valeur:
CWE-636: Not Failing Securely ('Failing Open') - When the product encounters an error condition or failure, its design requires it to fall back to a state that is less secure than other options that a...
📊 ENRICHISSEMENT 22/03/2026 05:01
REDHAT
Champ modifié: Sévérité Red Hat
Ancienne valeur:
N/A
Nouvelle valeur:
{ "threat_severity": "Moderate", "severity_scale": null }
📊 ENRICHISSEMENT 22/03/2026 05:01
REDHAT
Champ modifié: Red Hat
Ancienne valeur:
Non
Nouvelle valeur:
Oui
Total des modifications: 4 Dernière mise à jour: 1 week ago

> REFERENCES

https://github.com/pyca/pyopenssl/blob/358cbf29c4e364c59930e53a270116249581eaa3/...
https://github.com/pyca/pyopenssl/commit/d41a814759a9fb49584ca8ab3f7295de49a85aa...
https://github.com/pyca/pyopenssl/security/advisories/GHSA-vp96-hxj8-p424
« BACK_TO_HOME