Cryptocurrency web miner scripts make into MSN portal through Advertising Platform AOL and create a large number of web miners. Hackers Modified the scripts of AOL advertising platform to launch a web miner program and most of the minor traffic linked to MSN[.]com in Japan.
Security researchers from Trend Micro Spotted a significant increase(108%) in the number of unique miners, the Sudden Spike is because of the effectiveness of the advertising platform.
The compromised advertisement was on the front page of the MSN and it uses to redirect the user’s to the number of other pages. Further analysis shows more than 500 websites compromised with the same campaign.
When a user visit’s the MSN portal and if the advertisement is displayed, then their browser starts running cryptocurrency web miner and it stops after the user closes the browser window.
The malicious script was injected into advertising[.]aolp[.]jp and the web miner traffic linked to the domain www[.]jqcdn[.]download that was created on March 18.
Cryptocurrency mining script generated based on the Coinhive and attackers users private mining pools, possibly to avoid charges of using well-established miner’s.
“We closely examined compromised sites that this campaign modified and noticed that much of the malicious content was hosted on Amazon Web Service (AWS) S3 buckets. The names of the S3 buckets were visible in some of the compromised URLs, allowing us to investigate them further. We found that the buckets were completely unsecured, left open for anyone to list, copy, and modify” researchers said.
According to Trend Micro “We suspect that the legitimate AWS administrator didn’t properly set the permissions of their S3 bucket, which allowed the attacker to modify the hosted content“.