Bug 2510015 (CVE-2026-67293)

Summary: CVE-2026-67293 FreeRDP: FreeRDP: Weakens TLS server authentication due to improper wildcard certificate hostname validation
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
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, 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.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2510316, 2510317    
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Description OSIDB Bzimport 2026-08-01 13:03:25 UTC 
FreeRDP before 3.29.0 (affected versions <= 3.28.0) contains an improper certificate hostname validation vulnerability. The TLS hostname matcher (tls_match_hostname() in libfreerdp/crypto/tls.c) treats a wildcard pattern such as *.example.com as matching any hostname ending in .example.com, so it incorrectly accepts a wildcard certificate for multi-label subdomains like a.b.example.com (which OpenSSL's X509_check_host() rejects). This weakens TLS server authentication under wildcard-certificate conditions.