CVE-2026-34582 (GCVE-0-2026-34582)

Vulnerability from cvelistv5 – Published: 2026-04-07 21:13 – Updated: 2026-06-30 12:09
VLAI
Title
Botan has a TLS 1.3 certificate authentication bypass
Summary
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.
Severity
8.7 (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
9.1 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-841 - Improper Enforcement of Behavioral Workflow
  • CWE-166 - Improper Handling of Missing Special Element
Assigner
References
Impacted products
Vendor Product Version
randombit botan Affected: < 3.11.1
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Red Hat Red Hat Enterprise Linux 10     cpe:/o:redhat:enterprise_linux:10
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Show details on NVD website
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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