Plenty Of Fish users are at risk of contracting a malware infection on their computers.
This is due to an ad that was run on the dating site last week, which may have dropped malware on to user devices.
The malvertising attack was first spotted by Internet security firm Malewarebytes, who announced the findings on its official security blog.
The advertising network used the Google URL shortener, “goo.gl” to direct PoF users to the infected area, known as an Nuclear exploit kit.
The kit then infects devices by exploiting common vulnerable plug-ins, including Adobe Flash Player, Adobe Reader and Java.
The blog states: “The ad network involved in the malvertising campaign (ad.360yield.com) was familiar and it turns out that we had observed it in a rare attack captured by our honeypots just one day prior.”
Particularly at risk are those who do not have sufficient antivirus software installed on their computers.
Malwarebytes confirmed that anyone using its Anti-Exploit software were protected against the attack, and contacted the site to make them aware of the issue.
PlentyOfFish users are being advised to scan their computer systems for any signs of malware, and to ensure they use an effective antivirus system.
Read the full blog post here.