---
id: CVE-2026-109240
title: >-
  FreeRDP 3.11.0 before 3.32.1 contains a reachable assertion vulnerability in
  urb_isoch_transfer that allows malicious RDP servers to crash clients by
  sending unvalidated OutputBufferSize values
summary: >-
  FreeRDP 3.11.0 before 3.32.1 contains a reachable assertion vulnerability in
  urb_isoch_transfer that allows malicious RDP servers to crash clients by
  sending unvalidated OutputBufferSize values. Attackers can send a
  TS_URB_ISOCH_TRANSFER…
severity: low
cvss: 3.1
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:L'
cwe:
  - CWE-617
published: '2026-10-12'
updated: '2026-10-12'
sourceUpdated: '2026-10-12T17:17:14.720'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-109240'
references:
  - url: 'https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-9qqc-m43j-g4r2'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/freerdp-3.11.0-before-3.32.1-reachable-assertion-dos-via-urb-isoch-transfer
    label: disclosure@vulncheck.com
tags:
  - nvd
ingestedAt: '2026-10-12T18:00:08.172Z'
---

## Overview

FreeRDP 3.11.0 before 3.32.1 contains a reachable assertion vulnerability in urb_isoch_transfer that allows malicious RDP servers to crash clients by sending unvalidated OutputBufferSize values. Attackers can send a TS_URB_ISOCH_TRANSFER IN-direction request with OutputBufferSize above INT32_MAX over URBDRC, triggering an assertion in libusb_udev_isoch_transfer that terminates the client.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.