FreeRDP CVE-2026-109953

Exploitation requires that the victim invoke FreeRDP (3.0.0 through 3.31.x) with the /restricted-admin option AND connect to a destination that is either attacker-controlled or subject to a man-in-the-middle on the RDP/CredSSP channel - this is the specific prerequisite captured by AT:P and UI:P in the CVSS 4.0 vector. The core defect is that the /restricted-admin feature, whose entire purpose is to prevent credential delegation, does not suppress CredSSP delegation, so the cleartext password is sent regardless. Limiting factors: the attacker must already hold a privileged network position or own the target host, the user must actively start a restricted-admin session, and the flaw yields only credential disclosure (no code execution or integrity/availability impact). Deployments that never use restricted-admin mode, or that only connect to trusted/authenticated servers, are not practically exposed.

This is a credential-disclosure flaw (CWE-522) in FreeRDP's /restricted-admin code path, confirmed by the FreeRDP project (GHSA-jhxw-3hj9-9hqh) and reported by VulnCheck. The only severity signal provided is a CVSS 4.0 base score of 6.0 (Medium) with vector AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:N/VA:N - network-reachable and unauthenticated, but gated by an attack requirement (AT:P) and passive user interaction (UI:P), with impact limited to confidentiality (VC:H) and no integrity or availability effect. No EPSS probability, no CISA KEV listing, and no public POC were provided in the input, so exploitation likelihood cannot be quantified from the data; per the precision rule this is 'no public exploit identified at time of analysis.' The signals are internally consistent rather than conflicting: the AT:P and UI:P metrics correctly reflect that an attacker cannot exploit this at will - they need either a man-in-the-middle position on the RDP path or control of the destination host, AND a victim who connects using /restricted-admin. The real-world danger is that this feature is specifically intended to prevent credential delegation (that is its security purpose), so operators relying on it have a false sense of safety; the disclosed values are reusable administrative domain credentials, which elevates the practical impact above a typical info-leak even though CVSS caps it at Medium. Net: a credible, patch-worthy issue for environments using restricted-admin mode, but not a drop-everything emergency absent evidence of active exploitation.

An administrator connects with FreeRDP using the /restricted-admin option - expecting their password NOT to be sent to the target - to a host that is attacker-controlled or sitting behind a man-in-the-middle on the RDP channel. Because the option fails to suppress CredSSP delegation, the client transmits the cleartext password; the malicious endpoint decodes the TSPasswordCreds structure and Client Info PDU to recover reusable administrative domain, username, and password values. No public exploit was identified in the provided data, and the attack requires the privileged MITM/compromised-host position plus the victim initiating the connection.