Description
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.
Affected products
freerdp: freerdp
References3
- github.com/FreeRDP/FreeRDP/security/advisories/GHSA-5wr6-8m8j-3… ExploitVendor Advisory
- github.com/FreeRDP/FreeRDP/commit/f3b4347105114fe7453828736bea0… Patch
- www.vulncheck.com/advisories/freerdp-before-improper-certificat… Third Party Advisory
Metrics
- CVSS 3.1
-
4.2
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N - CVSS 4.0
-
9.3
CRITICAL
Score source: CNA
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 15 · as of 13 November 2026
- CWE
- CWE-295
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