Questions left unanswered about Yahoo malware attack

On Saturday, Fox IT, a security firm in the Netherlands, discovered that some visitors to Yahoo.com over the last few days have been infected with malware. Visitors to pages with malicious ads were redirected to sites armed with code that exploits vulnerabilities in Java and installs a variety of different malware.

Following news of the exploit, Yahoo has issued two statements to the press, but so far nothing on its public Tumblr blog, where it provides updates on products and services. On Saturday, a Yahoo spokesperson said: