CVE-2026-67294Network attack vectorHinoki check available

Server impersonation via clientAuth certificate acceptance

Published Aug 1, 2026 · Updated Aug 1, 2026

Improper certificate validation in FreeRDP before 3.29.0 allows remote attackers to impersonate an RDP server using a clientAuth certificate. x509_utils_verify() continues with client-purpose and any-purpose checks after server-purpose verification fails, accepting a certificate unsuitable for server authentication. Exploitation requires a trusted issuing chain and a hostname match, and it compromises server identity in environments that separate client and server EKUs.

CVSS severity5.9
Medium
EPSS probability0.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
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Summary

What happened

Improper certificate validation in FreeRDP before 3.29.0 allows remote attackers to impersonate an RDP server using a clientAuth certificate. x509_utils_verify() continues with client-purpose and any-purpose checks after server-purpose verification fails, accepting a certificate unsuitable for server authentication. Exploitation requires a trusted issuing chain and a hostname match, and it compromises server identity in environments that separate client and server EKUs.

The record

CVE
CVE-2026-67294
Published
Aug 1, 2026
Updated
Aug 1, 2026
Vendor
FreeRDP
Product
FreeRDP
Classifications
CWE-295, T1557
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 1, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 1, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <3.29.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

FreeRDP · FreeRDPversion=0 <3.29.0

Published CVSS scores

5.9CVE.orgCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
3.7Red HatCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-295Improper Certificate Validation
T1557Adversary-in-the-Middle

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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