Bug 2509999 (CVE-2026-67294)

Summary: CVE-2026-67294 FreeRDP: FreeRDP: Server certificate validation bypass via improper Extended Key Usage (EKU) validation
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in FreeRDP. During client-side server Transport Layer Security (TLS) authentication, FreeRDP improperly validates the Extended Key Usage (EKU) purpose of the peer certificate. This vulnerability allows a certificate intended only for client authentication to be accepted as a server certificate, bypassing critical server certificate purpose validation. This could lead to an attacker presenting a clientAuth-only certificate from a trusted Certificate Authority (CA) to impersonate a legitimate server.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Bug Depends On: 2510311, 2510312    
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Description OSIDB Bzimport 2026-08-01 13:02:33 UTC
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.