CVE-2026-32884: CWE-295: Improper Certificate Validation in randombit botan
CVE-2026-32884 is a medium severity vulnerability in the Botan C++ cryptography library prior to version 3. 11. 0. The issue involves improper certificate validation related to name constraints in X. 509 certificate path processing. Specifically, when an end-entity certificate lacks a subject alternative name (SAN), Botan checked the common name (CN) against DNS name constraints in a case-sensitive manner, which is not required by RFC 5280. This allowed certificates with mixed-case CN values to bypass excludedSubtrees constraints, potentially permitting unauthorized certificates to be accepted. The vulnerability has been patched in Botan version 3. 11. 0.
AI Analysis
Technical Summary
Botan versions before 3.11.0 improperly validated X.509 certificate name constraints by performing a case-sensitive comparison of the common name (CN) against DNS name constraints when no subject alternative name (SAN) was present. This behavior deviated from RFC 5280 requirements and allowed a certificate with a mixed-case CN (e.g., Sub.EVIL.COM) to bypass excludedSubtrees constraints for domains like evil.com. The vulnerability is classified under CWE-295 (Improper Certificate Validation) and has a CVSS 3.1 base score of 5.9 (medium severity). The issue was addressed and fixed in Botan version 3.11.0.
Potential Impact
The vulnerability could allow an attacker to present a certificate with a mixed-case common name that bypasses DNS name constraints, potentially enabling unauthorized certificates to be accepted by applications relying on Botan for certificate validation. This could lead to improper trust decisions and potential man-in-the-middle or spoofing attacks. However, no known exploits are reported in the wild.
Mitigation Recommendations
Users of Botan should upgrade to version 3.11.0 or later, where this certificate validation issue has been fixed. Since this is a library vulnerability, applying the official patch by updating the library version is the recommended remediation. There are no vendor advisories indicating that no action is required or that the issue is otherwise mitigated.
CVE-2026-32884: CWE-295: Improper Certificate Validation in randombit botan
Description
CVE-2026-32884 is a medium severity vulnerability in the Botan C++ cryptography library prior to version 3. 11. 0. The issue involves improper certificate validation related to name constraints in X. 509 certificate path processing. Specifically, when an end-entity certificate lacks a subject alternative name (SAN), Botan checked the common name (CN) against DNS name constraints in a case-sensitive manner, which is not required by RFC 5280. This allowed certificates with mixed-case CN values to bypass excludedSubtrees constraints, potentially permitting unauthorized certificates to be accepted. The vulnerability has been patched in Botan version 3. 11. 0.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Botan versions before 3.11.0 improperly validated X.509 certificate name constraints by performing a case-sensitive comparison of the common name (CN) against DNS name constraints when no subject alternative name (SAN) was present. This behavior deviated from RFC 5280 requirements and allowed a certificate with a mixed-case CN (e.g., Sub.EVIL.COM) to bypass excludedSubtrees constraints for domains like evil.com. The vulnerability is classified under CWE-295 (Improper Certificate Validation) and has a CVSS 3.1 base score of 5.9 (medium severity). The issue was addressed and fixed in Botan version 3.11.0.
Potential Impact
The vulnerability could allow an attacker to present a certificate with a mixed-case common name that bypasses DNS name constraints, potentially enabling unauthorized certificates to be accepted by applications relying on Botan for certificate validation. This could lead to improper trust decisions and potential man-in-the-middle or spoofing attacks. However, no known exploits are reported in the wild.
Mitigation Recommendations
Users of Botan should upgrade to version 3.11.0 or later, where this certificate validation issue has been fixed. Since this is a library vulnerability, applying the official patch by updating the library version is the recommended remediation. There are no vendor advisories indicating that no action is required or that the issue is otherwise mitigated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-03-16T21:03:44.421Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 69cae2bce6bfc5ba1d6c3e48
Added to database: 3/30/2026, 8:53:16 PM
Last enriched: 4/7/2026, 10:50:18 AM
Last updated: 5/14/2026, 11:03:54 PM
Views: 85
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