Not Failing Securely ('Failing Open') Affecting py3-openssl package, versions <26.1.0-r0


Severity

Recommended
0.0
medium
0
10

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Threat Intelligence

EPSS
0.04% (13th percentile)

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  • Snyk IDSNYK-ALPINE323-PY3OPENSSL-16300381
  • published27 Apr 2026
  • disclosed18 Mar 2026

Introduced: 18 Mar 2026

CVE-2026-27448  (opens in a new tab)
CWE-636  (opens in a new tab)

How to fix?

Upgrade Alpine:3.23 py3-openssl to version 26.1.0-r0 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream py3-openssl package and not the py3-openssl package as distributed by Alpine. See How to fix? for Alpine:3.23 relevant fixed versions and status.

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.

CVSS Base Scores

version 3.1