Is M3U8 Downloader safe?

Medium risk

M3U8 Downloader fetches and merges HLS video segments from user-supplied URLs and saves them locally as .ts or .mp4 files.

The extension's options page accepts an M3U8 playlist URL, fetches each .ts segment in parallel (up to 6 concurrent threads), and concatenates them into a single file downloaded through the browser. AES-128 encrypted streams are supported via a bundled decryptor. The options page HTML includes an ad-network script tag (sillinesswoollen.com) and Google Analytics and Microsoft Clarity integrations, all of which are blocked from executing by the manifest's strict content security policy.

HelloWorldv1.2.11Chrome Web Store
47Risk
Who publishes it

HelloWorld - 2 other listings from the same operator, none carrying a finding

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

Publisher
HelloWorld

Same store account

2 other listings published from this account, 90k+ users between them, none of them carrying a finding.

Shared hosts - 1 hostname

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.

m3u8.dev
Also called by 1 other listing: M3U8 Downloader Pro

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

Publishers can request a review.

Findings

Options Page References a Blocked Remote Script

MediumunwantedCWE-829Dynamic sandbox

M3U8 Downloader's options page references a remote script at sillinesswoollen.com.

What actually happens

You did this

You open the extension's options page.

The extension did this

The page contains a remote script reference that Chrome blocks under the extension's declared script policy.

Concrete fields in the shipped options page and manifest

  • Remote script host
    sillinesswoollen.com

    This names the outside site the options page points to.

  • Remote script path
    //sillinesswoollen.com/6a981008087a0a519c722c43126e8e0b/invoke.js

    This is the exact script location embedded in the page.

  • Options page
    index.html

    This is the extension page that contains the remote script reference.

  • Script policy
    script-src 'self'; object-src 'self'

    This browser-enforced rule allows extension-page scripts only from the extension package.

  • Host permission scope
    https://*/*

    Shows the extension can access HTTPS pages broadly, though the blocked options-page script does not run under the shipped policy.

Captured request

GET//sillinesswoollen.com/6a981008087a0a519c722c43126e8e0b/invoke.js

Chrome blocks the remote script on the extension page under the declared content security policy; no body was recorded.

The code that does this

The shipped options page contains the remote script, and the manifest blocks it

Readable version

Options page script tags

index.html
<body>  <div id="app"></div>  <script    async="async"    data-cfasync="false"    src="//sillinesswoollen.com/6a981008087a0a519c722c43126e8e0b/invoke.js"  ></script></body>

Extension page and script policy

manifest.json
{  "options_ui": {    "page": "index.html",    "open_in_tab": true  },  "background": {    "service_worker": "background.js"  },  "host_permissions": ["https://*/*"],  "content_security_policy": {    "extension_pages": "script-src 'self'; object-src 'self'"  }}

External hosts named by this evidence

    • sillinesswoollen.com

    Remote script host referenced from the extension options page.

What it can do

Permissions this extension asks for, as declared in version 1.2.11. 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 secure site you visit

    https://*/*

Updated 30 September 2026iflojgibfliebjepfhbbhaiaagdedoej