Botan has a TLS 1.3 certificate authentication bypass_CVE-2026-34582

8.7 / 10

HIGH

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

Description

Botan is a C++ cryptography library. Prior to version 3.11.1, the TLS 1.3 implementation allowed ApplicationData records to be processed prior to the Finished message being received. A server which is attempting to enforce client authentication via certificates can by bypassed by a client which entirely omits Certificate, CertificateVerify, and the Finished message and instead sends application data records. This vulnerability is fixed in 3.11.1.

Basic Information

ID CVE-2026-34582

Source GitHub_M

Published Apr 7, 2026 at 21:13

Modified Apr 8, 2026 at 15:41

Affected Product

Vendor randombit

Product botan

Version < 3.11.1

Affected Versions randombit botan < 3.11.1

CWE Classification

CWE-841

References

github.com /randombit/botan/security/advisories/GHSA-pxcj-9ppx-g86g

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