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CVE-2026-93601

Description

A flaw was found in rustls-webpki. This component incorrectly processes DNS (Domain Name System) name constraints for certificates asserting a wildcard name. This could allow a misissued wildcard certificate to be accepted for a domain that should be outside its permitted scope. Consequently, this bypass of name constraints could lead to incorrect certificate validation, potentially enabling an attacker to spoof a legitimate domain or perform man-in-the-middle attacks if they can obtain and use such a misissued certificate.

Statement

This vulnerability is rated as having a Low impact because exploitation demands strict preconditions, notably obtaining a cryptographically valid wildcard certificate that has been improperly issued by an authority subject to name constraints. Although multiple Red Hat offerings embed rustls-webpki for certificate path validation, the vulnerable evaluation occurs only after cryptographic signature checks succeed. Consequently, this flaw cannot be leveraged for arbitrary certificate spoofing without an existing trust misconfiguration or CA compromise.

Mitigation

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score2.2N/A2.2
Attack VectorNetworkN/ANetwork
Attack ComplexityHighN/AHigh
Privileges RequiredHighN/AHigh
User InteractionNoneN/ANone
ScopeUnchangedN/AUnchanged
ConfidentialityNoneN/ANone
Integrity ImpactLowN/ALow
Availability ImpactNoneN/ANone

Vector

Red Hat: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:L/A:N

cve.org: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:L/A:N

Frequently Asked Questions

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