NULL pointer dereference in FreeRDP - CVE-2026-121402
Published: November 10, 2026 / Updated: November 11, 2026
Vulnerability identifier: #VU164434
CSH Severity: Medium
CVSS v4: 6.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-121402
CWE-ID: CWE-476
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service by crashing a connected FreeRDP Linux X11 client.
The vulnerability exists due to a null pointer dereference in FreeRDP's graphics handling when a zero-width ResetGraphics request frees the primary display surface and replacement creation fails, leaving subsequent bitmap painting without a valid surface. A remote attacker can lure a victim into connecting to a malicious RDP server and send a zero-width RDPGFX ResetGraphics PDU followed by a normal bitmap update to crash the client.
Affected software
FreeRDP
How to mitigate CVE-2026-121402
Install security update from vendor's website.
FreeRDP - update to 3.32.2