CVE-2026-27459
pyOpenSSL is a Python wrapper around the OpenSSL library.
Published Mar 18, 2026 · updated Sep 10, 2026 · pyopenssl pyopenssl
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 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.
Code
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Timeline
Detection, updates, and resolution for this record.
Mar 18, 2026 · NIST NVD
Detected
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 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.
Sep 10, 2026 · NIST NVD
Updated
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 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.
Affected
- cpe pyopenssl/pyopensslversion unspecified
Sources
- CVE.orgVulnerability recordCVE-2026-27459
Official CVE identifier
cve.org - NIST NVDVulnerability recordCVE-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 returned a cookie value greater than 256 bytes, pyOpenSSL would overflow an OpenSSL provided buffer. Sta
nvd.nist.gov