Who is legally responsible for malware delivered through an ad on a website, the website or the ad network?
<p>Forbes recently started to block people who use an adblocker from accessing their website. The irony is that only a couple of days later, the ad network they use started spreading malware, ransomware to be exact, through the ads.</p>

<p>Suppose a Forbes user gets ransomware because of malicious ads on the Forbes website and loses important data (or at least valuable time while restoring the backup).</p>

<ol>
<li><p>Who is responsible for the malware infection?</p>

<ul>
<li>Forbes, because they're the website the user visited?</li>
<li>The ad network that provided a vector for infection and didn't properly check their content?</li>
<li>Or the makers of the ad, because they made the ad with malicious intent?</li>
</ul></li>
<li><p>Can the user sue the responsible party for damages?</p></li>
<li><p>Does it make a difference whether the user has taken due diligence with software updates and patches?</p></li>
</ol>

<p>The main jurisdictions I wonder about are Belgium and the USA.</p>

<p>There is no real answer to that question at this point.</p>
<p>If on filed such a suit, it would probably be under a negligence theory.  You would sue:</p>
<blockquote>
<p>Forbes, because they're the website the user visited?</p>
<p>The ad network that provided a vector for infection and didn't properly check their content?</p>
<p>The makers of the ad, because they made the ad with malicious intent?</p>
</blockquote>
<p>and anyone else who might have been negligent. You then have to prove they were negligent.</p>
<blockquote>
<p>Can the user sue the responsible party for damages?</p>
</blockquote>
<p>You can sue anyone for anything. The problem is winning.</p>
<blockquote>
<p>Does it make a difference whether the user has taken due diligence with software updates and patches?</p>
</blockquote>
<p>It might. Contributory negligence would be an obvious defense to such a suit.</p>

united-states internet advertisements belgium