Hackers broke into an advertising supply chain infecting visitors to an adult website.

Sky News reports that the large scale attack took place on the website PornHub affecting visitors around the world, according to the cybersecurity firm Proofpoint.

The attack called malvertising involved hackers hijack advertising platforms to deliver fake browser updates for the three most popular Windows browsers.

The Sky News report said that because advertising inventory can appear on high-profile websites, criminals are increasingly attempting to hijack these platforms to inject malware into a large number of victims' computers.

The cyber criminals create fake advertisements that would appear as security warnings on the Chrome, Firefox and Edge web browsers, informing users they needed to apply a critical update.

The report says PornHub acted swiftly when notified to counter the threat.