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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-27448 Detail

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  GitHub, Inc.
CVSS-BT 1.7 LOW
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

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/pyca/pyopenssl/blob/358cbf29c4e364c59930e53a270116249581eaa3/CHANGELOG.rst#L27 GitHub, Inc.
https://github.com/pyca/pyopenssl/commit/d41a814759a9fb49584ca8ab3f7295de49a85aa0 GitHub, Inc.
https://github.com/pyca/pyopenssl/security/advisories/GHSA-vp96-hxj8-p424 GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-636 Not Failing Securely ('Failing Open') GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-27448
NVD Published Date:
03/17/2026
NVD Last Modified:
03/17/2026
Source:
GitHub, Inc.