"We alerted Match.com and the related advertisers but the malvertising campaign is still ongoing via other routes."
The attack follows the now infamous Ashley Madison hacking saga, which saw 37 million adulterers' personal information leaked online.
The adultery website, whose tagline is "Life is short. Have an affair," is owned by Avid Life Media, responsible for Established Men, Swappernet (a swingers' site) and The Big and the Beautiful (a site for larger singles).
One document leaked by The Impact Team included the website's source code, which reveals interactions between users. Upon analysis, the code made clear that Ashley Madison's developers had created fake female profiles - or bots - to interact and entice men into paying to use the service.
Additional reporting by Sam Shead.
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