CVE-2026-34580

Botan is a C++ cryptography library. In 3.11.0, the function Certificate_Store::certificate_known had a misleading name; it would return true if any certificate in the store had a DN (and subject key identifier, if set) matching that of the argument. It did not check that the cert it found and the cert it was passed were actually the same certificate. In 3.11.0 an extension of path validation logic was made which assumed that certificate_known only returned true if the certificates were in fact identical. The impact is that if an end entity certificate is presented, and its DN (and subject key identifier, if set) match that of any trusted root, the end entity certificate is accepted immediately as if it itself were a trusted root. , This vulnerability is fixed in 3.11.1.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/randombit/botan/security/advisories/GHSA-v782-6fq4-q827	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:botan_project:botan:3.11.0:*:*:*:*:*:*:*

History

17 Apr 2026, 20:30

Type	Values Removed	Values Added
References	~~() https://github.com/randombit/botan/security/advisories/GHSA-v782-6fq4-q827 -~~	() https://github.com/randombit/botan/security/advisories/GHSA-v782-6fq4-q827 - Vendor Advisory
CPE		cpe:2.3:a:botan_project:botan:3.11.0:::::::*
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5
First Time		Botan Project botan Botan Project

07 Apr 2026, 22:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-07 22:16

Updated : 2026-04-17 20:30

NVD link : CVE-2026-34580

Mitre link : CVE-2026-34580

CVE.ORG link : CVE-2026-34580

JSON object : View

Products Affected

botan_project

botan

CWE

CWE-295

Improper Certificate Validation

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