Posted By: ITWiser Webmaster - Yorkshire's IT Specialists
Millions of Yahoo! Users Hit By Malware Attack
If you are a regular visitor to Yahoo.com, you may have inadvertently exposed your system to malware designed to steal personal information.
In yet more news of a major malware attack, security experts from Dutch firm Fox-IT are estimating that as many as two million European Yahoo! users may have been hit by malware disguised within advertisements served by Yahoo!’s official ads.yahoo.com service.
Fox-IT found that Great Britain was among the countries most affected by the attack and estimated that tens of thousands of computers were affected every hour.
“Given a typical infection rate of 9%, this would result in around 27,000 infections every hour,” according to this blog post.
“Based on the same sample, the countries most affected by the exploit kit are Romania, Great Britain, and France. At this time it is unclear why those countries are most affected; it is likely due to the configuration of the malicious advertisements on Yahoo!”
Yahoo! has confirmed that it is aware of the attack, which was first spotted on December 30, and has moved to block the malicious ads.
“We recently identified an ad designed to spread malware to some of our users. We immediately removed it and will continue to monitor and block any ads being used for this activity,” Yahoo! said in a statement.
While only a small percentage of advertisements were infected, the size of the site and the sheer number of visitors to Yahoo.com on a daily basis allowed the malware to have a massive impact. The objective of the attack is to exploit Java and plant a host of different malware, including Andromeda and the infamous ZeuS banking Trojan.
Advert Blocking and Content Filtering
As noted by The Register, security experts have long advised about the risks of using Java in Web browsers and this attack adds further weight to the argument that Web users should disable the technology.
For computers connected to a network, the risk of being exposed to malware is heightened by the ability that a virus has to spread to other systems. To avoid falling victim to such an exploit, users of multiple computers are advised to take advantage of ITWiser’s Cloud Web Security software, and the Advert Blocking feature in particular. URL Content Filtering also recommended as a way to protect users and systems from malicious content by restricting which websites can and cannot be visited during specific hours.
To find out more about how ITWiser can help you stay safe against the threat of malware, contact us on 01274 868924 or via email: info [at] ITwiser.co.uk.