Botan: Case-Insensitive CN Values Bypass DNS excludedSubtrees Name Constraints (RFC 5280 Violation) (randombit botan)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.17 % · percentile 6 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- GitHub_M
- NVD status
- Analyzed
Description
Botan is a C++ cryptography library. Prior to version 3.11.0, during processing of an X.509 certificate path using name constraints which restrict the set of allowable DNS names, if no subject alternative name is defined in the end-entity certificate Botan would check that the CN was allowed by the DNS name constraints, even though this check is technically not required by RFC 5280. However this check failed to account for the possibility of a mixed-case CN. Thus a certificate with CN=Sub.EVIL.COM and no subject alternative name would bypasses an excludedSubtrees constraint for evil.com because the comparison is case-sensitive. This issue has been patched in version 3.11.0.
Weaknesses (CWE)
- CWE-295 — Improper Certificate Validation
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | MEDIUM 5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N | GitHub_M |
| CVSS 3.1 | MEDIUM 5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N | NVD · security-advisories@github.com (Secondary) |
European references
- ENISA EUVD · EUVD-2026-17212
- GCVE · GCVE-0-2026-32884
Affected configurations (NVD CPE)
cpe:2.3:a:botan_project:botan:*:*:*:*:*:*:*:*< 3.11.0
Affected products
| Product | Versions |
|---|---|
| randombit · botan | affected < 3.11.0 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |