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VULNERABILITIES

CVE-2026-27459 Details

Description

pyOpenSSL is a Python wrapper around the OpenSSL library. Starting in version 22.0.0 and prior to version 26.0.0, if a user provided callback to `set_cookie_generate_callback` returned a cookie value greater than 256 bytes, pyOpenSSL would overflow an OpenSSL provided buffer. Starting in version 26.0.0, cookie values that are too long are now rejected.

Metrics

CVSS 3.x Severity and Vector Strings:

NIST: [email protected]CVSS-B:9.8 CRITICALVector:CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA: redhat-SADPCVSS-B:8.1 HIGHVector:CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

References to Advisories, Solutions, and Tools

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URLSource(s)Tag(s)
https://access.redhat.com/errata/RHSA-2026:10754 redhat-SADP
https://access.redhat.com/errata/RHSA-2026:11856 redhat-SADP
https://access.redhat.com/errata/RHSA-2026:11916 redhat-SADP
https://access.redhat.com/errata/RHSA-2026:11996 redhat-SADP
https://access.redhat.com/errata/RHSA-2026:13508 redhat-SADP

see all 26 references

Weakness Enumeration

CWE-IDCWE NameSource
CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')redhat-SADP
CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')[email protected]

Affected Products

ProductVersions
pyopenssl pyopenssl
>= 22.0.0, < 26.0.0

CPE

  • cpe:2.3:a:pyopenssl:pyopenssl:*:*:*:*:*:*:*:*

Remediation

  • No remediation found in references.

Change History

18 change records found show changes

QUICK INFO

CVE Dictionary Entry:
CVE-2026-27459
NVD Published Date:
Mar 18, 2026
NVD Last Modified:
Sep 10, 2026
Source:
[email protected]
CVE-2026-27459 Details - Not Deferred