CVE-2026-56297 · Symaro Security Advisory

Description

FreeRDP before 3.22.0 contains a use-after-free vulnerability in dvcman_channel_close and dvcman_call_on_receive due to improper synchronization of channel_callback access. A malicious RDP server can trigger a race condition by sending DYNVC_DATA and DYNVC_CLOSE messages concurrently, causing heap-use-after-free in the drdynvc client thread and potentially enabling remote code execution or denial of service.

Severity (CVSS)

Base score	8.3
Severity	High
Version	CVSS 4.0
Vector	CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N
Provided by	CNA

Weaknesses

CWE-362 — Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

Affected products

Vendor	Product	Versions
FreeRDP	FreeRDP	0 to <3.22.0; 3.22.0

References

https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-3mv2-5q57-2v8h (vendor-advisory)
https://www.vulncheck.com/advisories/freerdp-use-after-free-via-race-condition-in-drdynvc-channel-callback (third-party-advisory)

Authoritative sources

This page is a snapshot. For the latest enrichment and updates, view the record on CVE.org or the NVD.

Generated from the official CVE List on 09 Jul 2026 07:08 UTC.