FreeRDP 3.0.0 before 3.32.0 contains an improper certificate validation vulnerability in freerdp_http_request() in libfreerdp/utils/http.c that completes TLS handshakes without verifying the server certificate chain. On-path attackers can impersonate login.microsoftonline.com in the Azure AD authentication flow to capture OAuth authorization codes and substitute the OpenID discovery document.
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-h44v-39x6-9xvg
Published: 2026-10-12
Updated: 2026-10-14
Base Score: 7.1
Vector: CVSS2#AV:N/AC:H/Au:N/C:C/I:C/A:N
Severity: High
Base Score: 6.8
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
Severity: Medium
Base Score: 7.4
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
Severity: High
EPSS: 0.00187