CVE-2026-121393

A flaw was found in FreeRDP. A malicious Remote Desktop Protocol (RDP) server can cause a Denial of Service (DoS) by sending crafted RemoteFX graphics data to a connecting client. When the client processes malformed region rectangle coordinates, an internal assertion failure occurs, abruptly terminating the client application.

Red Hat has evaluated this issue as having a Moderate severity impact because exploitation is limited to a client crash and requires the user to initiate a connection to a rogue or compromised Remote Desktop host. The flaw does not facilitate arbitrary code execution, privilege escalation, or data leakage on the client system. Additionally, enterprise client installations are not exposed as listening network services, which restricts the attack surface to outbound sessions against untrusted targets.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.