Description
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.30.0, FreeRDP server-side RDSTLS in libfreerdp/core/rdstls.c accepts an attacker-supplied RDSTLS_TYPE_CAPABILITIES PDU while rdstls_server_authenticate is waiting for RDSTLS_TYPE_AUTHREQ, leaving resultCode at RDSTLS_RESULT_SUCCESS and allowing a remote unauthenticated client to bypass the RedirectionGuid, username, domain, or password checks. This issue is fixed in version 3.30.0.
Published: 2026-08-11
Score: 8.3 High
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Impact

FreeRDP’s RDSTLS server fails to enforce the proper sequence of protocol messages. A remote client can send a Capability PDU at the wrong stage, causing the server to accept the exchange as successful and skip credential checks, thereby granting unauthenticated access to the RDP session.

Affected Systems

The flaw affects the FreeRDP project, specifically all versions released before 3.30.0. Any deployment running those versions is vulnerable.

Risk and Exploitability

The CVSS score of 8.3 categorizes the vulnerability as high severity. EPSS indicates a very low likelihood of exploitation, and it is not listed in the CISA KEV catalog. Based on the description, it is inferred that the attack vector is remote, network‑based, and requires no pre‑existing authentication credentials. An attacker could contact the RDSTLS endpoint over the network and trigger the bypass to establish a session without authenticating.

Generated by OpenCVE AI on August 12, 2026 at 20:45 UTC.

Remediation

No vendor fix or workaround currently provided.

OpenCVE Recommended Actions

  • Upgrade FreeRDP to version 3.30.0 or later, which implements proper authentication sequencing.
  • If an upgrade is not immediate, block or restrict traffic to the RDSTLS port from untrusted networks using firewalls or access lists.
  • Deploy additional network monitoring to detect RDSTLS messages that deviate from the expected sequence and alert on potential bypass attempts.

Generated by OpenCVE AI on August 12, 2026 at 20:45 UTC.

Tracking

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Advisories

No advisories yet.

History

Thu, 13 Aug 2026 15:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Thu, 13 Aug 2026 12:15:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

 cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N'}

threat_severity

Important

Wed, 12 Aug 2026 13:45:00 +0000

Type Values Removed Values Added
First Time appeared Freerdp
Freerdp freerdp
Vendors & Products Freerdp
Freerdp freerdp

Tue, 11 Aug 2026 20:00:00 +0000

Type Values Removed Values Added
Description FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.30.0, FreeRDP server-side RDSTLS in libfreerdp/core/rdstls.c accepts an attacker-supplied RDSTLS_TYPE_CAPABILITIES PDU while rdstls_server_authenticate is waiting for RDSTLS_TYPE_AUTHREQ, leaving resultCode at RDSTLS_RESULT_SUCCESS and allowing a remote unauthenticated client to bypass the RedirectionGuid, username, domain, or password checks. This issue is fixed in version 3.30.0.
Title FreeRDP: RDSTLS server authentication bypass: a credential-less Capabilities PDU is accepted at the auth step (fail-open `resultCode`)
Weaknesses CWE-287
References
Metrics cvssV4_0

{'score': 8.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N'}

Subscriptions

Freerdp Freerdp
cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-08-13T14:51:02.290Z

Reserved: 2026-08-11T17:18:01.597Z

Link: CVE-2026-73241

cve-icon Vulnrichment

Updated: 2026-08-13T14:50:55.528Z

cve-icon NVD

Status : Received

Published: 2026-08-11T20:18:49.117

Modified: 2026-08-13T15:20:11.993

Link: CVE-2026-73241

cve-icon Redhat

Severity : Important

Publid Date: 2026-08-11T19:47:27Z

Links: CVE-2026-73241 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-08-12T21:00:04Z

Weaknesses