Critical severity · published Feb 25, 2026
CVE-2026-25955
FreeRDP has heap-use-after-free in xf_AppUpdateWindowFromSurface (stale XImage)
9.8
CVSS
0.6%
EPSS
No
On KEV
Description
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.23.0, `xf_AppUpdateWindowFromSurface` reuses a cached `XImage` whose `data` pointer references a freed RDPGFX surface buffer, because `gdi_DeleteSurface` frees `surface->data` without invalidating the `appWindow->image` that aliases it. Version 3.23.0 fixes the issue.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 47% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FR
FreeRDP · FreeRDP
< 3.23.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-25955
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-25955
Patch
https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_window.c#L1484-L1492
Patch
https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_window.c#L1494-L1500
Patch
https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_window.c#L1528
Patch
https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/libfreerdp/gdi/gfx.c#L1224-L1227
Patch
https://github.com/FreeRDP/FreeRDP/commit/169d358734509e82663a0d6a0085ae726d439d8e
Exploit
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-4g54-x8v7-559x
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