CVE-2026-27459 (GCVE-0-2026-27459)
Vulnerability from cvelistv5
Published
2026-03-17 23:34
Modified
2026-03-18 19:52
Severity ?
7.2 (High) - CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U
CWE
  • CWE-120 - Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
Summary
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.
References
Impacted products
Vendor Product Version
pyca pyopenssl Version: >= 22.0.0, < 26.0.0
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