CVE-2026-109939

A flaw was found in FreeRDP. A malicious or compromised Remote Desktop Protocol (RDP) server can cause a Denial of Service (DoS) by crashing the client application during connection establishment. By sending a specially crafted bitmap cache order before connection initialization completes, the server triggers a null pointer dereference in the client parser. This issue prevents users from establishing remote desktop connections when bitmap caching features are enabled.

This flaw is rated Moderate because a malicious or compromised RDP server can crash the FreeRDP client when Cache Bitmap V3 order handling is used, causing a denial of service for the connecting user. Exploitation requires the user to initiate a connection (UI:R). Confidentiality and integrity are not impacted. Red Hat platform safeguards such as ASLR, NX, and FORTIFY_SOURCE do not remove the crash impact, so Availability remains High.

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.

Restrict FreeRDP clients to trusted RDP servers and networks.