Vulnerability · Published Jul 8, 2026 · Assigned by VulnCheck
CVE-2026-56297FreeRDP - Use-After-Free via Race Condition in DRDYNVC Channel Callback
High 7.0
In plain English
A high-severity race condition in FreeRDP from FreeRDP. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 40% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | freerdp2 | no fix listed | DEBIAN-CVE-2026-56297 |
| Debian:13 | freerdp3 | no fix listed | DEBIAN-CVE-2026-56297 |
| Debian:14 | freerdp3 | 3.22.0+dfsg-1 | DEBIAN-CVE-2026-56297 |
| Ubuntu:22.04:LTS | freerdp2 | no fix listed | UBUNTU-CVE-2026-56297 |
| Ubuntu:24.04:LTS | freerdp3 | 3.30.0+dfsg-0ubuntu0.24.04.1 | USN-8561-1 |
| Ubuntu:24.04:LTS | freerdp3 | 3.30.0+dfsg-0ubuntu0.24.04.1 | UBUNTU-CVE-2026-56297 |
| Ubuntu:25.10 | freerdp3 | no fix listed | UBUNTU-CVE-2026-56297 |
| Ubuntu:26.04:LTS | freerdp3 | 3.30.0+dfsg-0ubuntu0.26.04.1 | USN-8561-1 |
Affected products (as reported)
Weakness: CWE-362 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H
References
- GitHub Security Advisory (GHSA-3mv2-5q57-2v8h) vendor-advisory
- VulnCheck Advisory: FreeRDP - Use-After-Free via Race Condition in DRDYNVC Channel Callback third-party-advisory