What’s Vulnerable › Vulnerabilities

CVE-2026-25953: FreeRDP has heap-use-after-free in xf_AppUpdateWindowFromSurface (freed appWindow)

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.7% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-02-25 · updated 2026-06-17
• Weakness: CWE-416

Description

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.23.0, `xf_AppUpdateWindowFromSurface` reads from a freed `xfAppWindow` because the RDPGFX DVC thread obtains a bare pointer via `xf_rail_get_window` without any lifetime protection, while the main thread can concurrently delete the window through a fastpath window-delete order. Version 3.23.0 fixes the issue.

Affected products

• FreeRDP: before 3.23.0 — fixed in 3.23.0

How to fix

Upgrade to a fixed version: FreeRDP 3.23.0. Check the vendor advisory for mitigations.

References

• https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_rail.c#L1230-L1237
• https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_rail.c#L257-L290
• https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_rail.c#L643-L647
• https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_window.c#L1394-L1428
• https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_window.c#L1462-L1470
• https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_window.c#L1484-L1491
• https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/libfreerdp/gdi/gfx.c#L254-L286
• https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/libfreerdp/gdi/gfx.c#L278-L279
• https://github.com/FreeRDP/FreeRDP/commit/1994e9844212a6dfe0ff12309fef520e888986b5
• https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-p6rq-rxpc-rh3p
• https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-p6rq-rxpc-rh3p

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