Online marketplace Trade Me was targeted by cybercriminals on Thursday and Friday last week.
In a statement, Trade Me notes: "A malicious advertisement purporting to be for Lonely Planet was detected on the site on Thursday and Friday. This “malvertisement” is a combination of malicious software and advertising, where cybercriminals use an online advertisement to distribute malicious software.
"If a member viewed the advertisement with an out-of-date browser or operating system, and had out-of-date anti-virus software, they may have been invited to download a program purporting to be “anti-virus” software. Only users that downloaded this malicious software will have been affected.
"Trade Me advised its members of the issue with the advertisement via a blog announcement and posts on the Trade Me message boards on Friday."
Trade Me spokesman Paul Ford said the company was aware of five people that had downloaded the malicious software and had their computers affected. “As soon as we became aware of the attack we took down the advertising tile and advised our members. So far 47 members have contacted us however most of those have not been affected,” Ford says.
The statement continues: "The vast majority of Trade Me members will not have seen the advertisement or received the invitation to download the infected software.
Ford said it was the first time Trade Me had been successfully targeted by malvertising cybercriminals.
“We have processes in place to prevent ads like this appearing but unfortunately this one snuck through and we are gutted that it happened. At the moment we’re focused on helping our members and making sure it doesn’t happen again, but we have also reported the issue to the Police. We will be doing everything we can to nail the cybercriminals responsible.”
Trade Me says anyone who visited the Lonely Planet advertisement on Trade Me on Thursday or Friday should run a full anti-virus and anti-malware scan on their computer, using a program such as Microsoft Security Essentials.
Trade Me's advice:
What do I do if I downloaded the malicious software?
Anyone who has downloaded the malware, should run a full anti-virus and anti-malware scan on their computer.
What do I do if I‘m not sure?
Anyone with an out-of-date browser or operating system or that does not have current anti-virus software should go to www.microsoft.com/security_essentials/ and follow the advice set out there.
What are your tips for staying safe from these types of attacks?
We recommend that everyone takes the following steps to keep safe online:
Make sure your browser is up-to-date.
Make sure your operating system is up-to-date.
Make sure you are using up-to-date anti-virus software.
Don’t download anything that looks remotely dodgy or that you aren’t sure about. If you are prompted to download something that doesn’t look legitimate while browsing Trade Me, report it to us ASAP via email abuse@trademe.co.nz
Where can I find more info on “malvertising”?
The information set out on Google’s anti-malvertising site is pretty useful, along with this article on Read Write Web.