CVE-2026-67293
Description
A flaw was found in FreeRDP, a free implementation of the Remote Desktop Protocol (RDP). The software's Transport Layer Security (TLS) hostname matcher incorrectly validates wildcard certificates, allowing it to accept certificates for multi-label subdomains that should not be covered. This vulnerability could enable a remote attacker to impersonate a legitimate server, potentially compromising the authenticity of the connection. This weakens the overall security of TLS server authentication.
Statement
This Moderate flaw in FreeRDP weakens TLS server authentication by incorrectly validating wildcard certificates. The client's TLS hostname matcher accepts multi-label subdomains (e.g., a.b.example.com) for a single-level wildcard (e.g., *.example.com), which deviates from standard OpenSSL behavior. This could allow a malicious RDP server to impersonate a legitimate server if a client attempts to connect to a subdomain covered by an improperly validated wildcard certificate.
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 Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 4.2 | N/A | 4.2 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | High | N/A | High |
| Privileges Required | None | N/A | None |
| User Interaction | Required | N/A | Required |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | Low | N/A | Low |
| Integrity Impact | Low | N/A | Low |
| Availability Impact | None | N/A | None |
Vector
Red Hat: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N
cve.org: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N
Understanding the Weakness (CWE)
Integrity,Authentication
Technical Impact: Bypass Protection Mechanism; Gain Privileges or Assume Identity
When a certificate is invalid or malicious, it might allow an attacker to spoof a trusted entity by interfering in the communication path between the host and client. The product might connect to a malicious host while believing it is a trusted host, or the product might be deceived into accepting spoofed data that appears to originate from a trusted host.
Frequently Asked Questions
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