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CVE-2026-27459

NVD

https://nvd.nist.gov/vuln/detail/CVE-2026-27459

Severity

Unknown
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Summary

pyOpenSSL DTLS cookie callback buffer overflow

Description

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

Affected packages

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