Security analysts have detected an ongoing attack that uses a huge number of computers from across the Internet to commandeer servers that run the WordPress blogging application.

The unknown people behind the highly distributed attack are using more than 90,000 IP addresses to brute-force crack administrative credentials of vulnerable WordPress systems, researchers from at least three Web hosting services reported. At least one company warned that the attackers may be in the process of building a "botnet" of infected computers that's vastly stronger and more destructive than those available today. That's because the servers have bandwidth connections that are typically tens, hundreds, or even thousands of times faster than botnets made of infected machines in homes and small businesses.

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Already, HostGator has indicated that the burden of this mass attack is causing huge strains on websites, which come to a crawl or go down altogether. There are also indications that once a WordPress installation is infected it's equipped with a backdoor so that attackers can maintain control even after the compromised administrative credentials have been changed. In some respects, the WordPress attacks resemble the mass compromise of machines running the Apache Web server, which Ars chronicled 10 days ago.

http://arstechnica.com/security/2013/04/huge-attack-on-wordpress-sites-could-spawn-never-before-seen-super-botnet/

I think anybody with a Wordpress site, that they don't manage on a daily basis, is too busy back-peddling and scouring to read the article!