Is Litmus safe?

Low risk

Litmus lets same-page messages trigger uploads of the current page HTML to litmus.com using the stored API token.

On non-ESP pages, Litmus accepts same-window postMessage commands that can start a local test. That path copies the full page HTML and sends it to Litmus with the user's stored account token.

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

litmus-plugin-adminsv1.2.1Chrome Web Store
20Risk
Who publishes it

Litmus Software, Inc. - no other listings under this identity, 1 shared hostname

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

Publisher
litmus-plugin-admins
Declared legal entity
Litmus Software, Inc.
Registered address
675 Massachusetts Ave., 10th Floor, Cambridge, MA 02139, United States
Registered contact
Litmus Software, Inc.
Website
litmus.com/help/

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.

login.mailchimp.com
Also called by 6 other listings, including Auto Follow Up for Gmail™, Gmail Email Templates by cloudHQ, Templates

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 1.2.1. 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> and 1 more

  • Read and change your data on localhost

    http://localhost/*

  • Read and change your data on litmus.localhost

    *://litmus.localhost/*

  • Read and change your data on 127.0.0.1

    http://127.0.0.1/*

  • Read and change your data on adobe-campaign.com

    *://*.adobe-campaign.com/*

  • Read and change your data on experience.adobe.com

    *://experience.adobe.com/*

  • Read and change your data on mailchimp.com

    *://*.mailchimp.com/*

  • Read and change your data on campaignmonitor.com

    *://*.campaignmonitor.com/*

  • Read and change your data on createsend.com

    *://*.createsend.com/*

  • Read and change your data on exacttarget.com

    *://*.exacttarget.com/* and 1 more

  • Read and change your data on pardot.com

    *://*.pardot.com/*

  • Read and change your data on cloud.goacoustic.com

    *://cloud.goacoustic.com/*

  • Read and change your data on marketodesigner.com

    *://*.marketodesigner.com/*

  • Read and change your data on marketingcloudapps.com

    *://*.marketingcloudapps.com/*

  • Read and change your data on members.exacttarget.com

    *://members.exacttarget.com/*

  • Read and change your data on members.s1.exacttarget.com

    *://members.s1.exacttarget.com/Content/Email/*

  • Read and change your data on members.s2.exacttarget.com

    *://members.s2.exacttarget.com/Content/Email/*

  • Read and change your data on members.s3.exacttarget.com

    *://members.s3.exacttarget.com/Content/Email/*

  • Read and change your data on members.s4.exacttarget.com

    *://members.s4.exacttarget.com/Content/Email/*

  • Read and change your data on members.s5.exacttarget.com

    *://members.s5.exacttarget.com/Content/Email/*

  • Read and change your data on members.s6.exacttarget.com

    *://members.s6.exacttarget.com/Content/Email/*

  • Read and change your data on members.s7.exacttarget.com

    *://members.s7.exacttarget.com/Content/Email/*

  • Read and change your data on members.s8.exacttarget.com

    *://members.s8.exacttarget.com/Content/Email/*

  • Read and change your data on members.s9.exacttarget.com

    *://members.s9.exacttarget.com/Content/Email/*

  • Read and change your data on members.s10.exacttarget.com

    *://members.s10.exacttarget.com/Content/Email/*

  • Read and change your data on members.s11.exacttarget.com

    *://members.s11.exacttarget.com/Content/Email/*

  • Read and change your data on members.s12.exacttarget.com

    *://members.s12.exacttarget.com/Content/Email/*

  • Read and change your data on members.s13.exacttarget.com

    *://members.s13.exacttarget.com/Content/Email/*

  • Read and change your data on members.s14.exacttarget.com

    *://members.s14.exacttarget.com/Content/Email/*

  • Read and change your data on members.s15.exacttarget.com

    *://members.s15.exacttarget.com/Content/Email/*

  • Read and change your data on eloqua.com

    *://*.eloqua.com/*

  • Read and change your data on eloquaeditors.com

    *://*.eloquaeditors.com/*

  • Read and change your data on user-content.s1.sfmc-content.com

    *://user-content.s1.sfmc-content.com/*

  • Read and change your data on user-content.s2.sfmc-content.com

    *://user-content.s2.sfmc-content.com/*

  • Read and change your data on user-content.s3.sfmc-content.com

    *://user-content.s3.sfmc-content.com/*

  • Read and change your data on user-content.s4.sfmc-content.com

    *://user-content.s4.sfmc-content.com/*

  • Read and change your data on user-content.s5.sfmc-content.com

    *://user-content.s5.sfmc-content.com/*

  • Read and change your data on user-content.s6.sfmc-content.com

    *://user-content.s6.sfmc-content.com/*

  • Read and change your data on user-content.s7.sfmc-content.com

    *://user-content.s7.sfmc-content.com/*

  • Read and change your data on user-content.s8.sfmc-content.com

    *://user-content.s8.sfmc-content.com/*

  • Read and change your data on user-content.s9.sfmc-content.com

    *://user-content.s9.sfmc-content.com/*

  • Read and change your data on user-content.s10.sfmc-content.com

    *://user-content.s10.sfmc-content.com/*

  • Read and change your data on user-content.s11.sfmc-content.com

    *://user-content.s11.sfmc-content.com/*

  • Read and change your data on user-content.s12.sfmc-content.com

    *://user-content.s12.sfmc-content.com/*

  • Read and change your data on user-content.s13.sfmc-content.com

    *://user-content.s13.sfmc-content.com/*

  • Read and change your data on user-content.s14.sfmc-content.com

    *://user-content.s14.sfmc-content.com/*

  • Read and change your data on user-content.s15.sfmc-content.com

    *://user-content.s15.sfmc-content.com/*

  • Read and change your data on klaviyo.com

    *://*.klaviyo.com/*

  • See the address and title of every tab you have open

    tabs

  • Run its own code inside the pages you visit

    scripting

  • Store data in your browser

    storage

  • Read and change cookies, including the ones that keep you signed in

    cookies

  • Write to your clipboard

    clipboardWrite

  • Run hidden pages in the background

    offscreen

Where it sends data

Destinations our analysis observed Litmus contacting. Sending data somewhere is not a finding on its own - an extension that syncs your settings has to talk to its own server - but it is where your data can go, and who else it goes to.

  • litmus.com

    Litmus sends data to litmus.com. No other extension we have analysed sends data here.

Updated 30 September 2026makmhllelncgkglnpaipelogkekggpio