Improper validation of certificate with host mismatch in FreeRDP - #VU137824
Published: July 16, 2026
Vulnerability identifier: #VU137824
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: N/A
CWE-ID: CWE-297
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: FreeRDP
Affected software:
FreeRDP
FreeRDP
Detailed vulnerability description
The vulnerability allows a remote attacker to bypass tls server hostname validation.
The vulnerability exists due to improper certificate hostname validation in tls_match_hostname() when verifying wildcard tls certificates for multi-label hostnames. A remote attacker can present a crafted wildcard certificate to bypass tls server hostname validation.
This issue affects cases where a certificate for a single-label wildcard domain is incorrectly accepted for a hostname with multiple labels.
Remediation
Install security update from vendor's website.