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CVE-2026-67294 (GCVE-0-2026-67294)

Vulnerability from cvelistv5 – Published: 2026-08-01 12:22 – Updated: 2026-08-03 18:15
VLAI
Title
FreeRDP before 3.29.0 TLS Certificate EKU Bypass
Summary
FreeRDP before 3.29.0 improperly validates the Extended Key Usage (EKU) purpose of the peer certificate during client-side server TLS authentication. In x509_utils_verify(), when server-purpose (X509_PURPOSE_SSL_SERVER) verification fails, the code falls back to client-purpose and any-purpose verification, so a trusted, hostname-matching certificate valid only for clientAuth can be accepted as the RDP server certificate. In environments relying on EKU separation between client and server certificates, this allows a clientAuth-only certificate issued by a trusted CA to bypass server certificate purpose validation.
Severity
9.3 (Critical)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-03 18:15 UTC
CWE
  • CWE-295 - Improper Certificate Validation
Assigner
References
Impacted products
Vendor Product Version CPE status
FreeRDP FreeRDP Affected: 0 , < 3.29.0 (semver)
Unaffected: 3.29.0 (semver)
    cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-07-15 00:00
Credits
1121984919
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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