Attackers explain how an anti-spam defense became an AI weapon.

  • Snowcano@startrek.website
    link
    fedilink
    English
    arrow-up
    6
    ·
    1 day ago

    Just make a custom 404 page that returns 13 MBs of junk along with status code 200

    How would you go about doing this part? Asking for a friend who’s an idiot, totally not for me.

    • drkt@scribe.disroot.org
      link
      fedilink
      English
      arrow-up
      7
      ·
      edit-2
      1 day ago

      I use Apache2 and PHP, here’s what I did:

      in .htaccess you can set ErrorDocument 404 /error-hole.php https://httpd.apache.org/docs/2.4/custom-error.html

      in error-hole.php,

      <?php
      http_response_code(200);
      ?>
      <p>*paste a string that is 13 megabytes long*</p>
      

      For the string, I used dd to generate 13 MBs of noise from /dev/urandom and then I converted that to base64 so it would paste into error-hole.php

      You should probably hide some invisible dead links around your website as honeypots for the bots that normal users can’t see.

        • drkt@scribe.disroot.org
          link
          fedilink
          English
          arrow-up
          1
          ·
          16 hours ago

          They will see a long string of base64 that takes a quarter of a second longer to load then a regular page. If it’s important to you, you can make the base64 string invisible and add some HTML to make it appear as a normal 404 page.

        • owl@infosec.pub
          link
          fedilink
          English
          arrow-up
          3
          ·
          edit-2
          20 hours ago

          I don’t know a lot about this, but I would guess a normal user would like a message, that says something along the lines of “404, couldn’t find what you were looking for.” The status code and the links back to itself as well as the 13 MBs of noise should probably not irritate them. Hidden links should also not irritate normal users.

          • SatyrSack@feddit.org
            link
            fedilink
            English
            arrow-up
            2
            ·
            22 hours ago

            I also “don’t know a lot about this”, but I do know that your browser receiving a 200 means that everything worked properly. From what I can tell, this technique is replaces any and every 404 response with 200, thus tricking the browser (and therefore the user) into thinking the site is working as expected every time they run into a missing webpage on this site.

      • WolfLink@sh.itjust.works
        link
        fedilink
        English
        arrow-up
        1
        ·
        22 hours ago

        For the string, I used dd to generate 13 MBs of noise from /dev/urandom and then I converted that to base64 so it would paste into error-hole.php

        That string is going to end up being 17MB assuming it’s a utf8 encoded .php file