CVE-2026-56297 FreeRDP CVE debrief

Who should care

Users of FreeRDP before version 3.22.0, operators of RDP services, platform administrators, vulnerability management teams, and security teams should be aware of this vulnerability. They should assess their exposure, apply patches or mitigations, and monitor for suspicious RDP activity to prevent potential remote code execution or denial of service attacks.

Technical summary

The vulnerability exists in dvcman_channel_close and dvcman_call_on_receive due to improper synchronization of channel_callback access. A malicious RDP server can exploit this by sending DYNVC_DATA and DYNVC_CLOSE messages concurrently, leading to a heap-use-after-free condition in the drdynvc client thread. This could potentially enable remote code execution or denial of service attacks. The affected product is FreeRDP before version 3.22.0.

Defensive priority

High

Recommended defensive actions

• Apply patches or updates to FreeRDP to version 3.22.0 or later
• Implement compensating controls, such as monitoring for suspicious RDP activity
• Conduct inventory checks to identify affected systems
• Consider disabling DYNVC channel if not required
• Review and verify the affected scope and severity with the vendor
• Monitor relevant logs and detection systems for exposed assets
• Track exceptions and retest remediated assets

Evidence notes

The CVE record was published on 2026-07-08T14:17:16.360Z and was last modified on 2026-07-09T19:38:09.027Z. The NVD entry is currently Undergoing Analysis. There is limited information available about the vulnerability, and defenders should verify the affected scope and severity with the vendor. The CVE record and NVD entry provide official details, but additional sources may be needed to fully understand the vulnerability.

Official resources