CVE-2026-40033CWE-122

FreeRDP - Heap-buffer-overflow in gdi_CacheToSurface via rectangle validation bypass

High · published May 26, 2026

CVSS v4.0
8.6
EPSS
1%
Percentile
64.3
In the wild
Unconfirmed
What it is

FreeRDP before 3.26.0 contains a heap-buffer-overflow vulnerability in gdi_CacheToSurface that allows remote attackers to write out-of-bounds heap memory. The vulnerability occurs because rectangle validation clamps coordinates to UINT16_MAX but performs copy operations using unclamped cache entry dimensions, enabling malicious RDP servers to trigger large out-of-bounds writes and potentially achieve remote code execution or client crash.

The record
Technical detail
CVSS v4.0
8.6 · HIGH
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
EPSS
0.01062 · 64.3th percentile
Weakness
CWE-122 · Heap-based Buffer Overflow
Published
2026-05-26T14:08Z
EPSS history
Timeline
  • 26 MAY 14:08Z
    FreeRDP - Heap-buffer-overflow in gdi_CacheToSurface via rectangle validation bypass
    cvelistv5