CVE-2026-56297 FreeRDP - Use-After-Free via Race Condition in DRDYNVC Channel Callback
A malicious RDP server can trigger a race condition in FreeRDP leading to use-after-free, potentially enabling remote code execution or denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-56297?
CVE-2026-56297 is a high-severity use after free vulnerability in Freerdp Freerdp, published on 8 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
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.
Weakness: CWE-362
Which versions are affected by CVE-2026-56297?
It affects 1 product.
Products include Freerdp Freerdp.
How do I fix CVE-2026-56297?
Upgrade to a fixed version.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-56297 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-56297 exists.
Other vulnerabilities in Freerdp Freerdp
- CVE-2021-37594 Other in n/a
- CVE-2021-37595 Other in n/a
- CVE-2026-67305 FreeRDP Windows Client before 3.29.0 Heap Buffer Overflow via Cliprdr
- CVE-2026-66402 FreeRDP before 3.29.0 TLS Certificate Identity Validation Bypass
- CVE-2026-67289 FreeRDP before 3.29.0 HTTP Proxy Request Injection via Redirection
Sources
Also known as DEBIAN-CVE-2026-56297, GHSA-392f-f2j5-97qm, GHSA-3mv2-5q57-2v8h, UBUNTU-CVE-2026-56297.