Mysterious Script Appeared in Footer of 1 website, with No Unique Plugins

[lorraine]

lorraine

May 23, 2024 at 7:52 am

Sometime between now & the last 1-2 months (when I last checked Lighthouse), a mysterious new HTTP request started being called externally on my website. I checked every other website I host/run on the same server, and despite having multiple other ones with the exact same plugins running the exact same versions/WP version, only this website in specific was having the issue.

I only had this to go off of: “moz-extension://6424c1ba-4269-44a9-aa2e-0bd9554b01ca/js/app.js”

I have never used Moz products/extensions/etc. in my life, and since it only appears on 1 website of the 1/2 dozen I manage, with 0 unique aspects, I couldn’t figure out wtf was causing it. Finally was able to track down the source of the external HTTP call, and it was the following script hidden at the end of the contact details in the footer:

<script src=”moz-extension://6424c1ba-4269-44a9-aa2e-0bd9554b01ca/js/app.js” type=”text/javascript”></script>

I’ll attach pictures in the next reply privately, but I was able to remove it and everything is fine now.

What I’m wondering though, is:

1. Wtf was this? How do I determine the function of this random javascript? What was the purpose for it?

2. How do I prevent something like this from happening again?

I’m paranoid now since I have no idea how this happened in the first place, and therefore no idea how to prevent it from happening again, nor what harm it has/potentially still could cause.