In the latest installment of the #AskGoogleWebmasters video series, John Mueller tackles the topic of how Google chooses canonical URLs. Mueller says its common for websites to have multiple, unique URLs that lead to the same content. For example, there’s WWW and non-WWW versions of a URL. Another common configuration is when the homepage is accessible as index.html, or when upper and lowercase characters in URLs lead to the same pages. Hackers are reportedly exploiting vulnerabilities in over ten WordPress plugins in order to backdoor sites with rouge admin accounts. This is an escalation of an attack that was reported on back in July in which attackers were hijacking sites to serve ads, scams, and malicious app downloads. Now, the same hacker group is taking complete control of vulnerable sites using similar tactics. ZDNet reports as of August 20 the hacker group modified the malicious code planted on hacked sites.