CVE-2026-27459 — pyOpenSSL DTLS cookie callback buffer overflow
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` r…
Published: 2026-03-17 · CVSS: 7.2 · CVSS 4.0
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7