back to article Massive browser hijacking campaign infects 2.3M Chrome, Edge users

A Chrome and Edge extension with more than 100,000 downloads that displays Google's verified badge does what it purports to do: It delivers a color picker to users. Unfortunately, it also hijacks every browser session, tracks activities across websites, and backdoors victims' web browsers, according to Koi Security researchers …

  1. Claude Yeller

    They started clean

    There have been stories floating around about existing extensions and apps that were acquired, or bought, by malware makers who then ran the updates with malware inserts.

    It is not clear from the story that these aps were initially developed with the intention to convert them to Trojan Horses later. They could equally well have been bona fide apps that were taken over by the bad guys.

    1. IGotOut Silver badge

      Re: They started clean

      I'm with you on this one.

      You wouldn't wait years to update a program with malware. It's not just buyouts, but also abandoned software, with poor configuration and repositories.

      1. VoiceOfTruth Silver badge

        Re: They started clean

        I don't use any plugins or extensions personally. But this to me seems like Google and Microsoft have been seriously caught with their pants down. Instead of a one-time verified badge, they need a 'last verified date' badge. Even use traffic light colours: green <= 6 months ago.

        If we are constantly told to change passwords regularly, Google needs to regularly verify its store contents.

        1. lglethal Silver badge
          Trollface

          Re: They started clean

          Wait you want them to actually earn that 30% store commision????

          1. Diogenes8080

            Re: They started clean

            Looking at that list of extensions, I would hardly call them "trusted". Half seem to be for restriction evasion and at least one of the others is clearly fraudulent.

            This isn't new. Who else remembers Sourceforge turning from a valuable resource into a lake of trojan adware?

            But yeah, call it open-source malware, project takeover or simple schmuckery in the stores, very little of what's out there is reliable.

        2. Anonymous Coward Silver badge
          Boffin

          Re: They started clean

          Surely green = this version.

          Amber = within the last m months / n versions (whichever is shortest)

          Red = consider it unverified

    2. heyrick Silver badge

      Re: They started clean

      I think this is what happened with the ES File Explorer app. I don't tend to update my apps if they're working for me, and asides from the apps from my bank which are necessary, an app that *forces* an update by refusing to work tends to get uninstalled instead.

      Consequently I am using one of the last good versions of ES; and I have noticed along the way other apps that have changed owners to random sounding weird names that seem a bit sus.

      1. Irongut Silver badge

        Re: They started clean

        I switched to CX File Explorer and have been happy with it since.

      2. logicalextreme

        Re: They started clean

        ES lost me years ago, became absolute junk. I switched to MiXplorer and haven't looked back. Costs money (but would be worth it) if you want to install it via Google Play etc, otherwise it's free as APKs (modular, ish) and you can donate however you feel.

    3. wolfetone Silver badge

      Re: They started clean

      None of them vet the code that's submitted. That's the main problem.

      1. Stevie Silver badge

        Re: None of them vet the code that's submitted

        But with the facility afforded by A.I. they ...

        What?

    4. JoeCool Silver badge

      Re: They started clean

      It's not clear in the story, because no-one knows yet. Hence the "reaching out to the developer ..." part.

  2. Inkey
    Go

    Eh?

    "productivity tools"

    ...go away....

    ;)

  3. Anonymous Coward Silver badge
    Big Brother

    Colo(u)r picker

    Why would you install a browser extension for a colour picker? Surely everyone (on Windows) has PowerToys installed.

    [Win]+Shift+C

    Works everywhere, not just in the browser.

    1. logicalextreme

      Re: Colo(u)r picker

      Aye, or Instant Eyedropper as I used to use before PowerToys existed. It's crackers that you'd have it as a browser extension and give it access to various gubbins from the browser process(es). Makes you wonder if there's people installing browser extensions to tell them e.g. how much free disk space they have.

      1. FIA Silver badge

        Re: Colo(u)r picker

        It's crackers that you'd have it as a browser extension

        Why is it crackers?

        If you can answer without referencing anything vaguely technical that you know due to working in IT then it is crackers.

        But in reality for most people the browser is the thing they use to do stuff, it's 'add ons' are prominent. If I'm a regular computer user why wouldn't that be my first port of call for a widget to do a thing? I don't really understand computers, or the distinction around applications, I just have a tool I use as I was instructed. Do I care that a button over here launches a standalone app, or do I care that I can now do the thing I wanted to do?

        When I was in my 20s I used to chuckle at people who used CD ROM trays as cup holders, as they were stupid. Then I learnt to drive and found yet another set of cup holders in my car that I'd not noticed after 6 months (seriously... how many do people need?!?) it suddenly didn't seem such a stupid assumption after all. Most people knew CDs as music devices. Computers back then to most people didn't play music, they went 'beep'. So actually, a little slide out drawer didn't seem so out of place as a holder of temporary things.

        1. Anonymous Coward
          Anonymous Coward

          Re: Colo(u)r picker

          Ah yes, cupholders. Another one of thse fun standards. So you have this nice tin with dimensions that everyone shares, and everyone makes space for it in vehicles.

          So Cola Cola decide to do a thin one, of course. Muppets.

        2. Anonymous Coward Silver badge
          Holmes

          Re: Colo(u)r picker

          Your little story falls down on one major aspect. The "dumb users" don't want to know the specific colours, so have no need for such functionality.

          If they're the slightly more attuned dumb users (such the coloured pencil department) they'll be using different software (e.g. photoshop) that includes this functionality natively.

          Web developers will likely have the dev tools window open, etc...

    2. Stevie Silver badge

      Re: Colo(u)r picker

      "Surely everyone (on Windows)"

      Just answered your own question there.

  4. Anonymous Coward
    Anonymous Coward

    Pantone

    You want colours? Just get a Pantone Chart.

    1. Richard 12 Silver badge
      Trollface

      Re: Pantone

      Who's got that kind of money?

      1. John Brown (no body) Silver badge

        Re: Pantone

        The people who profit from trojan colour pickers? :-)

  5. venkatarangan

    Microsoft and Google should do more

    As users, we need to demand browser makers and extensions marketplaces run by Google and Microsoft do more. They need to share responsibility here. If they can't offer it free, they need to offer a paid subscription level, where they can offer validated extensions.

  6. WolfFan Silver badge

    Heh.

    At both the office and at the Large Educational Institution where I do some adjunct instruction, both Microsoft’s and Google’s stores are blocked, for security reasons, and getting to Apple’s store can be tedious, same reason. If you need something from Microsoft or Google’s stores, contact IT and they will evaluate it, test it, verify it, and, if it passes, let you have it. To get something from Apple merely means jumping through a lot of hoops. And updates are NOT automatically passed on. IT around here has long considered all those stores to be security risks. Especially the auto-update features, for precisely the reasons shown in the article.

  7. Pantagoon

    Google use one hand to kill off Ad Blockers that protect users from scams and then dish out malware to the masses with the other. Well done them.

    1. parrot

      “Malware to the masses”

      Chortle. A cynic might speculate this is a broader remit than you think.

  8. xyz Silver badge
    Joke

    Err..

    >But in addition to providing these legitimate functions, they secretly surveil users' web browsing activity, capturing URLs, sending this info to a remote attacker-controlled server along with the victim's unique tracking ID, and even redirecting people's browsers if instructed,

    Sounds like it was made by Google and Microsoft. Isnt that their day job?

  9. Tron Silver badge

    You forgot Windows.

    Started out fine, requiring just the number printed on the pack to prove it was legit. A few years of upgrades later it wants you to sign up with more ID info, includes Recall and has a direct line to the mothership.

    Sneaky stuff indeed.

  10. Grogan

    So much for the dumbed down Extension APIs in Chrome browsers being safer, eh?

  11. vekkq

    The main Dark Reader extension exists under another ID. These extensions may be partially or fully stolen.

  12. Nematode Bronze badge

    Surprised to see no post yet saying "what part of Firefox/Waterfox/Brave/Opera/Safari/<insert preferred browser of your choice> ... do you not understand?"

    1. Anonymous Coward
      Anonymous Coward

      Indeed, but the add-on repos for these other browsers could equally well have malware add-ons uploaded to them as well (and there certainly have been some known examples in the past of specific add-ons going rogue and not being discovered for a while).

      (Also, Opera these days is just yet another Chromium clone, and is now owned by a Chinese company and has a bit of a bad smell about it. Vivaldi, set up by some of the original Opera team, is perhaps its more appropriate current successor, although Vivaldi is also (sadly) mostly just yet another Chromium clone itself…)

    2. julian_n

      Ars Technica report Firefox also is affected:

      https://arstechnica.com/security/2025/07/browser-extensions-turn-nearly-1-million-browsers-into-website-scraping-bots/

      1. Nematode Bronze badge

        Thanks! Scans list of extensions on page linked at the foot of that....

  13. Anonymous Coward
    Anonymous Coward

    I'm missing Edge itself in that list..

    I mean, with all those updates..

    :)

  14. Anonymous Coward
    Anonymous Coward

    Then there was this news item last month......

    ....about other (possibly) dodgy stuff in the Google Store and the Apple Store:

    - https://www.theregister.com/2025/06/13/apple_google_chinabased_vpns/

    Did someone mention the word "trust"? Google, Apple, Microsoft, Meta........

  15. mpi

    And that's why I don't have any browser extensions installed.

    Browsers are probably one of the most critical pieces of software ever. They are networked super-applications, with capabilities that rival those of an OS. They have to execute code from random sources on purpose, and do so in a secure way. And we trust them with the most intimate and critical details of our lives.

    Ain't no way in hell I'm gonna exacerbate the risks involved in that by also running 3rd party code, that automatically eats changes done by god-knows-who, and has essentially privileged access to the Browser, on top of that.

    Yes, that costs me functionality. Boohoo. There is always a trade-off between comfort and security. I chose the latter.

    1. usbac

      Re: And that's why I don't have any browser extensions installed.

      What about ad blockers? While I agree on not loading a bunch of unknown code into my browser, the web is now unusable without an ad blocker.

  16. drewbuoy

    LOL, to review the Color Picker Tool in the Microsoft Store (say, to post a friendly warning?) Microsoft requires you to first INSTALL the extension.

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