---
id: CVE-2026-63117
title: FreeRDP is a free implementation of the Remote Desktop Protocol
summary: >-
  FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to
  3.28.0, an authenticated RDP client can advertise DVI ADPCM with nBlockAlign
  equal to 8 and nChannels equal to 2 to make the `bs` calculation in
  rdpsnd_server_sele…
severity: medium
cvss: 6.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-369
vendor: freerdp
product: freerdp
affected:
  - freerdp < 3.28.0
patched:
  - freerdp 3.28.0
published: '2026-08-19'
updated: '2026-09-24'
sourceUpdated: '2026-09-24T15:13:21.393'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-63117'
references:
  - url: >-
      https://github.com/FreeRDP/FreeRDP/commit/b78fc0b138fe8f08a8b102e193ffb32986f4449a
    label: security-advisories@github.com
  - url: 'https://github.com/FreeRDP/FreeRDP/pull/12980'
    label: security-advisories@github.com
  - url: 'https://github.com/FreeRDP/FreeRDP/releases/tag/3.28.0'
    label: security-advisories@github.com
  - url: 'https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-v64m-xxfw-hrv6'
    label: security-advisories@github.com
tags:
  - nvd
epss: 0.00548
epssPercentile: 0.43451
ingestedAt: '2026-09-09T21:22:45.541Z'
---

## Overview

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.28.0, an authenticated RDP client can advertise DVI ADPCM with nBlockAlign equal to 8 and nChannels equal to 2 to make the `bs` calculation in rdpsnd_server_select_format in channels/rdpsnd/server/rdpsnd_main.c equal zero. The subsequent out_frames modulo `bs` operation raises SIGFPE and terminates the server-side rdpsnd channel process. This vulnerability fixed in 3.28.0.

## Affected

- `freerdp < 3.28.0`

## Remediation

Upgrade past the affected range:

- `freerdp 3.28.0`