Логотип exploitDog
Консоль
Логотип exploitDog

exploitDog

redhat логотип

CVE-2026-27448

Опубликовано: 17 мар. 2026
Источник: redhat
CVSS3: 5.4
EPSS Низкий

Описание

A flaw was found in pyOpenSSL. The set_tlsext_servername_callback callback function can be used to implement Server Name Indication (SNI) during the TLS handshake. When the callback raises an unhandled exception, the handshake incorrectly proceeds instead of terminating. This fail-open behavior can allow an attacker to bypass SNI-based security controls and access restricted endpoints.

Отчет

This flaw is only exploitable when an application using the pyOpenSSL library provides a custom callback to the set_tlsext_servername_callback function. For the handshake to proceed incorrectly, the callback must raise an unhandled exception, limiting the exposure of this issue. Due to these reasons, this vulnerability has been rated with an important severity.

Меры по смягчению последствий

To mitigate this flaw, ensure the callback provided to the set_tlsext_servername_callback function is wrapped in a try/except block. This block should explicitly return a failure code instead of allowing the exception to propagate.

Затронутые пакеты

ПлатформаПакетСостояниеРекомендацияРелиз
Red Hat Ansible Automation Platform 2ansible-automation-platform-24/lightspeed-rhel8Fix deferred
Red Hat Ansible Automation Platform 2ansible-automation-platform-25/ee-supported-rhel8Fix deferred
Red Hat Ansible Automation Platform 2ansible-automation-platform-25/lightspeed-rhel8Fix deferred
Red Hat Ansible Automation Platform 2ansible-automation-platform-26/ansible-dev-tools-rhel9Fix deferred
Red Hat Ansible Automation Platform 2ansible-automation-platform-26/controller-rhel9Fix deferred
Red Hat Ansible Automation Platform 2ansible-automation-platform-26/eda-controller-rhel9Fix deferred
Red Hat Ansible Automation Platform 2ansible-automation-platform-26/ee-minimal-rhel9Fix deferred
Red Hat Ansible Automation Platform 2ansible-automation-platform-26/ee-supported-rhel9Fix deferred
Red Hat Ansible Automation Platform 2ansible-automation-platform-26/hub-rhel9Fix deferred
Red Hat Ansible Automation Platform 2ansible-automation-platform-26/lightspeed-rhel9Fix deferred

Показывать по

Дополнительная информация

Статус:

Moderate
Дефект:
CWE-636
https://bugzilla.redhat.com/show_bug.cgi?id=2448508pyOpenSSL: TLS connection bypass via unhandled callback exception in set_tlsext_servername_callback

EPSS

Процентиль: 11%
0.00038
Низкий

5.4 Medium

CVSS3

Связанные уязвимости

ubuntu
9 дней назад

(pyOpenSSL is a Python wrapper around the OpenSSL library. Starting in ...)

nvd
9 дней назад

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.

msrc
8 дней назад

pyOpenSSL allows TLS connection bypass via unhandled callback exception in set_tlsext_servername_callback

debian
9 дней назад

pyOpenSSL is a Python wrapper around the OpenSSL library. Starting in ...

github
10 дней назад

pyOpenSSL allows TLS connection bypass via unhandled callback exception in set_tlsext_servername_callback

EPSS

Процентиль: 11%
0.00038
Низкий

5.4 Medium

CVSS3