Improper certificate validation in PkixNameConstraintValidator in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an attacker who controls, or can obtain certificates from, a name-constrained intermediate CA to have certificates accepted during PKIX certification path validation for email addresses, DNS names or URI hosts that lie within excluded subtrees applying to that CA, via an rfc822Name, dNSName or uniformResourceIdentifier name whose host ends with a dot, because names and constraints were compared without first removing the RFC 1034 root-label trailing dot, so a fully qualified host name did not match an excluded subtree for the same host written without the dot.

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History

Sat, 03 Oct 2026 06:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Fri, 02 Oct 2026 07:30:00 +0000

Type Values Removed Values Added
Description Improper certificate validation in PkixNameConstraintValidator in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an attacker who controls, or can obtain certificates from, a name-constrained intermediate CA to have certificates accepted during PKIX certification path validation for email addresses, DNS names or URI hosts that lie within excluded subtrees applying to that CA, via an rfc822Name, dNSName or uniformResourceIdentifier name whose host ends with a dot, because names and constraints were compared without first removing the RFC 1034 root-label trailing dot, so a fully qualified host name did not match an excluded subtree for the same host written without the dot.
Title Name constraints bypass via trailing dot in rfc822Name, dNSName and URI hosts
Weaknesses CWE-295
References
Metrics cvssV4_0

{'score': 8.2, 'vector': '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'}


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cve-icon MITRE

Status: PUBLISHED

Assigner: bcorg

Published:

Updated: 2026-10-02T17:49:42.601Z

Reserved: 2026-09-30T23:01:10.053Z

Link: CVE-2026-103602

cve-icon Vulnrichment

Updated: 2026-10-02T17:49:38.169Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-10-02T08:17:00.677

Modified: 2026-10-02T18:17:00.407

Link: CVE-2026-103602

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-10-02T09:15:08Z

Weaknesses