Dutch security firm Fox IT discovered an ongoing malware-based attack that hit thousands of Yahoo users via malicious ads. Visitors most affected are located in Romania, Great Britain and France. Yahoo is aware of the ongoing malware attack and is taking necessary countermeasures to stop it in fact traffic to the server hosting the malicious exploit is decreasing since Friday evening. The hope is that Yahoo in the future will be able to protect the entire data flaw also related to third parties sites that propose ads through its channel.”]
Source: https://securityaffairs.co/wordpress/20972/malware/malware-served-yahoo-advertisements.html