Is Ruffle - Flash Emulator safe?

Low risk

Ruffle - Flash Emulator runs Flash content locally via WebAssembly and does not send browsing data to external servers.

The extension injects a content script on most pages to detect and replace legacy Flash embeds with its own WebAssembly-based player, allowing sites that still use Flash to function. All Flash execution happens locally; no URLs visited or page content are transmitted externally. A low-severity implementation issue allows page scripts on the same page to observe the internal postMessage session ID and redirect the Flash player to a URL of their choosing.

Part of this rating comes from analysis signals we haven't published as detailed findings yet.

Rufflev0.7.0.65535Firefox Add-ons
17Risk
Who publishes it

Ruffle - no other listings under this identity, 8 shared hostnames

What this publisher told the store about itself, and the other listings that told it the same thing.

Publisher
Ruffle
Website

Shared hosts - 8 hostnames

Hostnames hardcoded in this extension that few other listings call. That can mean one operator behind both, and it can equally mean a small shared vendor, so it is context rather than a conclusion. Hosts that many listings call are left out: they are services, not connections.

mydhl.express.dhl
Also called by 2 other listings, including Ruffle
my.4399.com
Also called by 3 other listings, including Ruffle
news.4399.com
Also called by 3 other listings, including Ruffle
sjsj.4399.com
Also called by 3 other listings, including Ruffle
sans.org
Also called by 4 other listings, including SuperNova SWF Enabler
4399.com
Also called by 5 other listings
authentication.td.com
Also called by 5 other listings, including Flash Player Emulator
tuxedocomputers.com
Also called by 5 other listings, including Flash Player Emulator

AI-generated. Findings may contain errors. Those marked Verified have been manually reviewed.

Publishers can request a review.

What it can do

Permissions this extension asks for, as declared in version 0.7.0.65535. Asking for a permission is not a finding on its own - it is what the extension can do if it chooses to.

  • Read and change your data on every site you visit

    <all_urls>

  • Store data in your browser

    storage

  • Run its own code inside the pages you visit

    scripting

declarativeNetRequestWithHostAccess
Updated 2 November 2026amo-2733133