Out-of-bounds read in FreeRDP - CVE-2026-66401
Published: July 16, 2026 / Updated: September 14, 2026
Vulnerability identifier: #VU137819
CSH Severity: Low
CVSS v4: 2.4 [CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-66401
CWE-ID: CWE-125
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows an attacker with physical access to cause a denial of service.
The vulnerability exists due to an out-of-bounds heap read in the UVC H.264 extension-unit parser in the rdpecam V4L client path when processing a crafted USB video-control interface extra descriptor during camera stream setup. An attacker with physical access can provide a malicious USB camera with a short extension-unit descriptor to cause a denial of service.
User interaction is required to use the redirected camera, and the issue is triggered when a V4L camera stream is created.
Affected software
FreeRDP
How to mitigate CVE-2026-66401
Install security update from vendor's website.
FreeRDP - update to 3.29.0