Improper Certificate Validation in Botan - CVE-2026-32884
Published: April 8, 2026
Vulnerability identifier: #VU125382
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-32884
CWE-ID: CWE-295
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Randombit
Affected software:
Botan
Botan
Detailed vulnerability description
The vulnerability allows a remote attacker to bypass DNS name constraints enforcement.
The vulnerability exists due to improper certificate validation in X.509 certificate path processing when validating a certificate chain with DNS excludedSubtrees constraints and an end-entity certificate that has a mixed-case CN and no subject alternative name. A remote attacker can present a specially crafted certificate to bypass DNS name constraints enforcement.
This issue is relevant when nameConstraints are used to restrict allowable DNS names.
How to mitigate CVE-2026-32884
Install security update from vendor's website.