Use-after-free in FreeRDP - CVE-2026-26986

Vulnerability identifier: #VU125352

CSH Severity: Low

CVSS v4: 7.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-26986

CWE-ID: CWE-416

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote user to cause a denial of service and potentially execute arbitrary code.

The vulnerability exists due to use-after-free in rail_window_free in the X11 RAIL window handling code when processing a server-supplied window create order and freeing RAIL window entries during disconnect. A remote user can send a specially crafted window order to cause a denial of service and potentially execute arbitrary code.

One server-triggered exploitation path requires the builtin Unicode backend to be enabled, where malformed UTF-16 window title data causes title conversion to fail and leaves a dangling hash table entry until disconnect.

FreeRDP
SUSE Linux Enterprise Server 12 SP5 LTSS Extended
SUSE Linux Enterprise Server 12 SP5
SUSE Linux Enterprise Server for SAP Applications 12
SUSE Linux Enterprise Server 12
SUSE Linux Enterprise High Performance Computing 12
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Workstation Extension 15
SUSE Linux Enterprise Desktop 15
SUSE Linux Enterprise Real Time 15
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for ARM 64
Red Hat CodeReady Linux Builder for x86_64
Red Hat CodeReady Linux Builder for Power, little endian
Red Hat CodeReady Linux Builder for ARM 64
Red Hat CodeReady Linux Builder for IBM z Systems
Anolis OS
Red Hat Enterprise Linux Server - AUS
Red Hat Enterprise Linux Server - TUS
Red Hat Enterprise Linux for ARM 64 - Extended Update Support
Red Hat Enterprise Linux for Power, little endian - Extended Update Support
Red Hat Enterprise Linux for IBM z Systems - Extended Update Support
Red Hat Enterprise Linux for x86_64 - Extended Update Support
SUSE Package Hub 15
openSUSE Leap
openEuler
Ubuntu
Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions
freerdp (Red Hat package)
freerdp-devel
winpr2-devel
freerdp-wayland-debuginfo
freerdp-server-debuginfo
freerdp-debugsource
uwac0-0-devel
freerdp-server
freerdp-wayland
libuwac0-0-debuginfo
libfreerdp2
libwinpr2-debuginfo
libwinpr2
freerdp
libuwac0-0
freerdp-proxy-debuginfo
libfreerdp2-debuginfo
freerdp-proxy
freerdp-debuginfo
libwinpr2-2-debuginfo
libfreerdp2-2
winpr-devel
libfreerdp2-2-debuginfo
libwinpr2-2
freerdp-libs
libwinpr
libwinpr-devel
freerdp-doc
freerdp2-debuginfo
freerdp2-proxy
freerdp2-devel
freerdp2
freerdp2-server-debuginfo
freerdp2-server
freerdp2-debugsource
freerdp2-proxy-debuginfo
freerdp-help
freerdp3 (Ubuntu package)
freerdp-proxy-plugins
freerdp-sdl-debuginfo
librdtk0-0
libfreerdp3-3-debuginfo
libfreerdp3-3
libfreerdp-server-proxy3-3
libfreerdp-server-proxy3-3-debuginfo
libwinpr3-3-debuginfo
freerdp-proxy-plugins-debuginfo
librdtk0-0-debuginfo
freerdp-sdl
libwinpr3-3

Install security update from vendor's website.

FreeRDP - update to 3.23.0
freerdp (Red Hat package) - addressed in versions 2.1.1-5.el7_9.9, 2.2.0-7.el8_6.8, 2.2.0-12.el8_8.8, 2.2.0-14.el8_4, 2.4.1-3.el9_0.7, 2.11.2-1.el9_4.8, 2.11.7-1.el9_6.10, 2.11.7-9.el8_10, 3.10.3-5.el10_1.8
freerdp-devel - addressed in versions 2.1.2-12.68.1, 2.4.0-150400.3.52.1, 2.11.2-150600.4.26.1, 3.10.3-150700.3.14.1
winpr2-devel - addressed in versions 2.1.2-12.68.1, 2.4.0-150400.3.52.1, 2.11.7-150700.3.22.1
freerdp-wayland-debuginfo - addressed in versions 2.4.0-150400.3.52.1, 2.11.2-150600.4.26.1, 3.10.3-150700.3.14.1
freerdp-server-debuginfo - addressed in versions 2.4.0-150400.3.52.1, 2.11.2-150600.4.26.1, 3.10.3-150700.3.14.1
freerdp-debugsource - addressed in versions 2.4.0-150400.3.52.1, 2.11.2-150600.4.26.1, 3.10.3-150700.3.14.1
uwac0-0-devel - addressed in versions 2.4.0-150400.3.52.1, 2.11.2-150600.4.26.1
freerdp-server - addressed in versions 2.4.0-150400.3.52.1, 2.11.2-150600.4.26.1, 3.10.3-150700.3.14.1
freerdp-wayland - addressed in versions 2.4.0-150400.3.52.1, 2.11.2-150600.4.26.1, 3.10.3-150700.3.14.1
libuwac0-0-debuginfo - addressed in versions 2.4.0-150400.3.52.1, 2.11.2-150600.4.26.1, 3.10.3-150700.3.14.1
libfreerdp2 - update to 2.4.0-150400.3.52.1
libwinpr2-debuginfo - update to 2.4.0-150400.3.52.1
libwinpr2 - update to 2.4.0-150400.3.52.1
freerdp - addressed in versions 2.4.0-150400.3.52.1, 2.11.2-150600.4.26.1, 3.10.3-150700.3.14.1
libuwac0-0 - addressed in versions 2.4.0-150400.3.52.1, 2.11.2-150600.4.26.1, 3.10.3-150700.3.14.1
freerdp-proxy-debuginfo - addressed in versions 2.4.0-150400.3.52.1, 2.11.2-150600.4.26.1, 3.10.3-150700.3.14.1
libfreerdp2-debuginfo - update to 2.4.0-150400.3.52.1
freerdp-proxy - addressed in versions 2.4.0-150400.3.52.1, 2.11.2-150600.4.26.1, 3.10.3-150700.3.14.1
freerdp-debuginfo - addressed in versions 2.4.0-150400.3.52.1, 2.11.2-150600.4.26.1, 3.10.3-150700.3.14.1
libwinpr2-2-debuginfo - addressed in versions 2.11.2-150600.4.26.1, 2.11.7-150700.3.22.1
libfreerdp2-2 - addressed in versions 2.11.2-150600.4.26.1, 2.11.7-150700.3.22.1
winpr-devel - addressed in versions 2.11.2-150600.4.26.1, 3.10.3-150700.3.14.1
libfreerdp2-2-debuginfo - addressed in versions 2.11.2-150600.4.26.1, 2.11.7-150700.3.22.1
libwinpr2-2 - addressed in versions 2.11.2-150600.4.26.1, 2.11.7-150700.3.22.1
freerdp-libs - update to 2.11.7-9.0.1
freerdp-devel - update to 2.11.7-9.0.1
freerdp - update to 2.11.7-9.0.1
libwinpr - update to 2.11.7-9.0.1
libwinpr-devel - update to 2.11.7-9.0.1
freerdp-doc - update to 2.11.7-9.0.1
freerdp2-debuginfo - update to 2.11.7-150700.3.22.1
freerdp2-proxy - update to 2.11.7-150700.3.22.1
freerdp2-devel - update to 2.11.7-150700.3.22.1
freerdp2 - update to 2.11.7-150700.3.22.1
freerdp2-server-debuginfo - update to 2.11.7-150700.3.22.1
freerdp2-server - update to 2.11.7-150700.3.22.1
freerdp2-debugsource - update to 2.11.7-150700.3.22.1
freerdp2-proxy-debuginfo - update to 2.11.7-150700.3.22.1
freerdp-debuginfo - update to 2.11.8-1
libwinpr - update to 2.11.8-1
freerdp-help - update to 2.11.8-1
libwinpr-devel - update to 2.11.8-1
freerdp - update to 2.11.8-1
freerdp-debugsource - update to 2.11.8-1
freerdp-devel - update to 2.11.8-1
freerdp3 (Ubuntu package) - addressed in versions 3.5.1+dfsg1-0ubuntu1.4, 3.16.0+dfsg-2ubuntu0.3
freerdp-proxy-plugins - update to 3.10.3-150700.3.14.1
freerdp-sdl-debuginfo - update to 3.10.3-150700.3.14.1
librdtk0-0 - update to 3.10.3-150700.3.14.1
libfreerdp3-3-debuginfo - update to 3.10.3-150700.3.14.1
libfreerdp3-3 - update to 3.10.3-150700.3.14.1
libfreerdp-server-proxy3-3 - update to 3.10.3-150700.3.14.1
libfreerdp-server-proxy3-3-debuginfo - update to 3.10.3-150700.3.14.1
libwinpr3-3-debuginfo - update to 3.10.3-150700.3.14.1
freerdp-proxy-plugins-debuginfo - update to 3.10.3-150700.3.14.1
librdtk0-0-debuginfo - update to 3.10.3-150700.3.14.1
freerdp-sdl - update to 3.10.3-150700.3.14.1
libwinpr3-3 - update to 3.10.3-150700.3.14.1

• https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-crqx-g6x5-rx47
• https://github.com/advisories/GHSA-crqx-g6x5-rx47

• Multiple vulnerabilities in FreeRDP
• openEuler 24.03 LTS update for freerdp
• openEuler 22.03 LTS SP4 update for freerdp
• openEuler 20.03 LTS SP4 update for freerdp
• openEuler 24.03 LTS SP3 update for freerdp
• openEuler 24.03 LTS SP2 update for freerdp
• openEuler 24.03 LTS SP1 update for freerdp
• Ubuntu update for freerdp3
• SUSE update for freerdp
• SUSE update for freerdp
• SUSE update for freerdp
• SUSE update for freerdp
• SUSE update for freerdp2
• Red Hat Enterprise Linux 10 update for freerdp
• Red Hat Enterprise Linux 8 update for freerdp
• Red Hat Enterprise Linux 9 update for freerdp
• Red Hat Enterprise Linux 8 update for freerdp
• Red Hat Enterprise Linux 8 update for freerdp
• Red Hat Enterprise Linux 9 update for freerdp
• Red Hat Enterprise Linux 9 update for freerdp
• Anolis OS update for freerdp
• Red Hat Enterprise Linux 8 update for freerdp
• Red Hat Enterprise Linux 7 Extended Lifecycle Support update for freerdp