---
id: CVE-2026-44421
title: FreeRDP is a free implementation of the Remote Desktop Protocol
summary: >-
  FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to
  3.26.0, a malicious RDP server can trigger a heap-buffer-overflow write in the
  FreeRDP client by sending crafted RDPGFX PDUs. The bug is in
  gdi_CacheToSurface: it …
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'
cwe:
  - CWE-122
  - CWE-787
vendor: freerdp
product: freerdp
affected:
  - freerdp < 3.26.0
patched:
  - freerdp 3.26.0
published: '2026-05-29'
updated: '2026-07-08'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-44421'
references:
  - url: 'https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-p6r2-4hgm-m6ff'
    label: security-advisories@github.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:36203'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: 'https://access.redhat.com/security/cve/CVE-2026-44421'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2483471'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: 'https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-p6r2-4hgm-m6ff'
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-44421.json
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
tags:
  - nvd
epss: 0.00717
epssPercentile: 0.51801
ingestedAt: '2026-07-08T13:51:10.778Z'
---

## Overview

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.26.0, a malicious RDP server can trigger a heap-buffer-overflow write in the FreeRDP client by sending crafted RDPGFX PDUs. The bug is in gdi_CacheToSurface: it validates a destination rectangle that is clamped to UINT16_MAX, but then performs the copy using the original cacheEntry->width/height. This can cause a large out-of-bounds heap write and may lead to client crashes or code execution. This bug is reachable from a malicious RDP server, but only when the client has RDPGFX enabled. This vulnerability is fixed in 3.26.0.

## Affected

- `freerdp < 3.26.0`

## Remediation

Upgrade past the affected range:

- `freerdp 3.26.0`