CVE-2026-93601

rustls-webpki (the Rust webpki fork used by rustls) versions >= 0.101.0 and prior to 0.103.12 and 0.104.0-alpha.6 incorrectly accepted permitted-subtree DNS name constraints for certificates asserting a wildcard name. For example, a name constraint of accept.example.com was treated as satisfied by a certificate for *.example.com, which could feasibly assert reject.example.com — a name outside the permitted subtree. Because name constraints are restrictions applied to otherwise properly issued certificates, the issue is only reachable after signature verification succeeds and requires a misissued wildcard certificate to exploit.

CVSS v3 2.2 LOW

2.2^/10

CVSS v3 : LOW

Vector :

Exploitability : 0.7 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/rustls/webpki/security/advisories/GHSA-xgp8-3hg3-c2mh
https://www.vulncheck.com/advisories/rustls-webpki-0.101.0-before-0.103.12-name-constraint-bypass

Configurations

No configuration.

History

18 Sep 2026, 14:19

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-18 14:19

Updated : 2026-09-22 20:25

NVD link : CVE-2026-93601

Mitre link : CVE-2026-93601

CVE.ORG link : CVE-2026-93601

JSON object : View

Products Affected

No product.

CWE

CWE-295

Improper Certificate Validation

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