CVE-2026-4344: Autodesk Fusion Stored XSS Vulnerability

CVE-2026-4344 Overview

CVE-2026-4344 is a Stored Cross-Site Scripting (XSS) vulnerability in the Autodesk Fusion desktop application. The flaw resides in the delete confirmation dialog, which fails to sanitize HTML content embedded in component names. An attacker who plants a maliciously crafted component name can trigger script execution when a user opens the delete dialog and interacts with it. Successful exploitation allows the adversary to read local files or execute arbitrary code in the context of the running Autodesk Fusion process. The issue is tracked under CWE-79 and documented in Autodesk Security Advisory ADSK-SA-2026-0005.

Critical Impact
Stored XSS in Autodesk Fusion can lead to local file read and arbitrary code execution in the user's process context.

Affected Products

Autodesk Fusion (desktop client) on Windows
Autodesk Fusion (desktop client) on macOS
Fusion Client Downloader installers distributed via dl.appstreaming.autodesk.com

Discovery Timeline

2026-04-14 - CVE-2026-4344 published to NVD
2026-04-22 - Last updated in NVD database

Technical Details for CVE-2026-4344

Vulnerability Analysis

The vulnerability is a Stored Cross-Site Scripting (XSS) flaw classified under [CWE-79]. Autodesk Fusion renders user-controllable component names inside an HTML-based delete confirmation dialog without proper output encoding. When a component name contains active HTML or JavaScript, that markup is interpreted by the dialog's rendering engine instead of being displayed as inert text.

Because Fusion is built on an embedded web technology stack, script executed inside the dialog runs with the privileges of the desktop application. This expands the impact beyond classic browser-based XSS. According to the advisory, an attacker can leverage the flaw to read local files or execute arbitrary code in the context of the current process. Exploitation requires user interaction: a victim must click within the delete confirmation dialog for the malicious payload to fire.

Root Cause

The root cause is missing HTML sanitization of the component name field when it is rendered into the delete confirmation dialog template. The application treats the stored name as trusted markup rather than as untrusted user data, violating standard output-encoding practice for HTML contexts.

Attack Vector

The attack vector is local and requires user interaction. An attacker first stores a malicious payload in a component name, typically by sharing a crafted Fusion design file or by modifying a shared project. When a victim opens the file and attempts to delete the tainted component, the dialog renders the payload and executes it on click. The resulting script runs with the user's privileges and can access local files or invoke OS-level functionality exposed to the Fusion process.

No verified public proof-of-concept code is available. See the Autodesk Security Advisory ADSK-SA-2026-0005 for vendor technical details.

Detection Methods for CVE-2026-4344

Indicators of Compromise

Autodesk Fusion design files or shared projects containing component names with HTML tags such as <script>, <img onerror=...>, or <iframe> constructs.
Unexpected child processes spawned by the Fusion desktop client (for example, cmd.exe, powershell.exe, or shell processes on macOS).
File read activity by the Fusion process against sensitive user directories outside its normal working paths.

Detection Strategies

Hunt across endpoint telemetry for process ancestry where Autodesk Fusion is the parent of script interpreters or scripting hosts.
Inspect shared Fusion project repositories and cloud workspaces for component name fields containing HTML control characters (<, >, ", ').
Correlate file open events for .f3d or shared design files with subsequent anomalous outbound network connections from the Fusion process.

Monitoring Recommendations

Enable endpoint detection and response (EDR) telemetry on workstations running Autodesk Fusion and alert on unusual child-process creation.
Log and review file access patterns from the Fusion process, focusing on user profile directories and credential stores.
Track installation and update events sourced from dl.appstreaming.autodesk.com to confirm patched versions are deployed.

How to Mitigate CVE-2026-4344

Immediate Actions Required

Update Autodesk Fusion to the fixed version referenced in ADSK-SA-2026-0005 on all Windows and macOS endpoints.
Avoid opening Fusion design files or shared projects received from untrusted sources until updates are applied.
Audit shared Fusion workspaces for components whose names contain HTML or scripting syntax and rename or remove them.

Patch Information

Autodesk has published guidance in Autodesk Security Advisory ADSK-SA-2026-0005. Updated installers are available via the Fusion Client Downloader for Windows and the Fusion Client Downloader for macOS. Administrators should redeploy Fusion using these official installers to ensure the patched dialog rendering code is in place.

Workarounds

Instruct users not to click within the delete confirmation dialog for components originating from untrusted designs; cancel the operation and rename the component through a safe interface instead.
Restrict sharing of Fusion projects to trusted collaborators and enforce review of imported component metadata.
Run Fusion under standard (non-administrative) user accounts to reduce the impact of arbitrary code execution within the process context.

bash

# Configuration example: verify installed Fusion version on macOS
/usr/bin/defaults read "/Applications/Autodesk Fusion.app/Contents/Info.plist" CFBundleShortVersionString

# Windows: list installed Fusion version via PowerShell
Get-ItemProperty "HKCU:\Software\Autodesk\Fusion 360\*" | Select-Object DisplayName, DisplayVersion