Search vulnerabilities

Use the Query Builder to create your own search query, or check out the documentation to learn the search syntax.

Results 2

Export CSV
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` 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 4.0 · 7.2 High EPSS < 1% KEV · Not listed
Vendors
Pyca Pyopenssl
Products
Pyopenssl Pyopenssl
CVE-2026-27448

pyOpenSSL allows TLS connection bypass via unhandled callback exception in set_tlsext_servername_callback

pyOpenSSL is a Python wrapper around the OpenSSL library. Starting in version 0.14.0 and prior to version 26.0.0, if a user provided callback to `set_tlsext_servername_callback` raised an unhandled exception, this would result in a connection being accepted. If a user was relying on this callback for any security-sensitive behavior, this could allow bypassing it. Starting in version 26.0.0, unhandled exceptions now result in rejecting the connection.

CVSS 4.0 · 1.7 Low EPSS < 1% KEV · Not listed
Vendors
Pyca Pyopenssl
Products
Pyopenssl Pyopenssl