CVE-2026-27459

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/pyca/pyopenssl/blob/358cbf29c4e364c59930e53a270116249581eaa3/CHANGELOG.rst
https://github.com/pyca/pyopenssl/commit/57f09bb4bb051d3bc2a1abd36e9525313d5cd408
https://github.com/pyca/pyopenssl/security/advisories/GHSA-5pwr-322w-8jr4

Configurations

No configuration.

History

18 Mar 2026, 14:52

Type	Values Removed	Values Added
Summary		(es) pyOpenSSL es un envoltorio de Python para la biblioteca OpenSSL. A partir de la versión 22.0.0 y antes de la versión 26.0.0, si una devolución de llamada proporcionada por el usuario a set_cookie_generate_callback devolvía un valor de cookie superior a 256 bytes, pyOpenSSL desbordaría un búfer proporcionado por OpenSSL. A partir de la versión 26.0.0, los valores de cookie que son demasiado largos ahora son rechazados.

18 Mar 2026, 00:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-18 00:16

Updated : 2026-03-18 14:52

NVD link : CVE-2026-27459

Mitre link : CVE-2026-27459

CVE.ORG link : CVE-2026-27459

JSON object : View

Products Affected

No product.

CWE

CWE-120

Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

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