CVE-2026-26986
Severity CVSS v4.0:
MEDIUM
Type:
CWE-416
Use After Free
Publication date:
25/02/2026
Last modified:
25/02/2026
Description
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.23.0, `rail_window_free` dereferences a freed `xfAppWindow` pointer during `HashTable_Free` cleanup because `xf_rail_window_common` calls `free(appWindow)` on title allocation failure without first removing the entry from the `railWindows` hash table, leaving a dangling pointer that is freed again on disconnect. Version 3.23.0 fixes the vulnerability.
Impact
Base Score 4.0
5.50
Severity 4.0
MEDIUM
References to Advisories, Solutions, and Tools
- https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_rail.c#L1230-L1238
- https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_rail.c#L1297
- https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_rail.c#L1316-L1327
- https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_rail.c#L386-L394
- https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_rail.c#L395-L399
- https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_rail.c#L401-L404
- https://github.com/FreeRDP/FreeRDP/commit/b4f0f0a18fe53aa8d47d062f91471f4e9c5e0d51
- https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-crqx-g6x5-rx47



