Server impersonation via overbroad wildcard matching
Published Aug 1, 2026 · Updated Aug 1, 2026
Improper certificate validation in FreeRDP before 3.29.0 allows remote attackers to impersonate RDP servers using trusted wildcard certificates. The tls_match_hostname() function in libfreerdp/crypto/tls.c accepts any hostname ending in a wildcard certificate's suffix, including multi-label names that the wildcard does not cover. The client must connect to such a multi-label hostname while the attacker can present a trusted wildcard certificate; acceptance weakens server authenticity and exposes the session to interception or alteration.
Summary
What happened
Improper certificate validation in FreeRDP before 3.29.0 allows remote attackers to impersonate RDP servers using trusted wildcard certificates. The tls_match_hostname() function in libfreerdp/crypto/tls.c accepts any hostname ending in a wildcard certificate's suffix, including multi-label names that the wildcard does not cover. The client must connect to such a multi-label hostname while the attacker can present a trusted wildcard certificate; acceptance weakens server authenticity and exposes the session to interception or alteration.
The record
- CVE
- CVE-2026-67293
- Published
- Aug 1, 2026
- Updated
- Aug 1, 2026
- Vendor
- FreeRDP
- Product
- FreeRDP
- Classifications
- CWE-295, CAPEC-459, CAPEC-475, T1557
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 1, 2026CVE publishedPublication date reported by the CVE source.
- 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.
- Affected versionversion=0 <3.29.0
What conditions does exploitation require?
What is affected?
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.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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