---
id: "CVE-2026-121395"
kind: "vulnerability"
aliases: ["CVE-2026-121395"]
title: "FreeRDP: malicious RDP server can crash client via RemoteFX tile"
severity: "high"
cvss: 7.1
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["freerdp", "linux", "package", "rdp", "remotefx", "windows"]
not_affected_if: ["assertions-disabled", "trusted-servers-only", "versions-outside-3.17.0-to-3.32.2"]
published_at: "2026-11-03T15:17:27+00:00"
first_seen_at: "2026-11-03T15:21:57+00:00"
updated_at: "2026-11-03T15:23:02+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-121395", "first_seen_at": "2026-11-03T15:21:57+00:00"}]
---

# FreeRDP: malicious RDP server can crash client via RemoteFX tile

FreeRDP's RemoteFX differential decoder fails an assertion when a malicious RDP server sends a crafted tile with out-of-range coefficients, aborting the client process. The sources describe a denial of service that only triggers when verbose WinPR assertions are enabled.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed FreeRDP version, for example with `xfreerdp /version`, and compare it to the affected range `3.17.0` to before `3.32.2`.
- Check whether verbose WinPR assertions are enabled in the build or the environment (unknown how to confirm from the sources).

## Fix

- Move to FreeRDP `3.32.2` or later.

## Timeline

- 2026-11-03T15:21:57+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-121395

## Documents

- [advisory] Vendor advisory: github.com https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-cg4f-57hc-v7w7
- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/freerdp-3.17.0-before-3.32.2-denial-of-service-via-remotefx-decoder

## From the sources

FreeRDP from 3.17.0 before 3.32.2 contains an assertion failure in the RemoteFX differential decoder when verbose WinPR assertions are enabled. A malicious RDP server can send a crafted RemoteFX tile with adjacent LL3 coefficients summing beyond signed 16-bit range to abort the client process.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_