CVE-2026-56297
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.
A public proof-of-concept or exploit code is available, raising the risk of active exploitation. No distribution fix is listed yet; apply vendor mitigations and monitor.
Recommended action: Track your distribution's security tracker and apply the fix as soon as it ships.
Severity metrics
CVSS 4.0 : 8.3 HIGH · CVSS 3.1 : 7.0 HIGH
Vector: AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N
Affected & fixed versions by distribution
Versions are the native distribution strings (backport-aware): RHEL/Debian/SUSE backport fixes, so compare with the distro version comparator (dpkg / rpm / vercmp), not the upstream version.
No affected package in the tracked watchlist yet (Debian, Ubuntu, Arch, SUSE, Red Hat...). Triage may still be pending.