Early July a security flaw has been discovered in the WordPress plugin MailPoet, otherwise known as the wysija-newsletters. As of July 23, 2014, the blog Sucuri informed that this flaw was exploited and publicly unveiled.

Vulnerability allows an attacker to compromise your WordPress site, or even the server that hosts it. This is why it is described as critical. According to information reported by the blog, this plugin use is widespread and the exploitation of the vulnerability already very extended: several thousand websites hacked in the aftermath of the dissemination of the fault.

If you use this plugin, we strongly invite you to update. All less than the 2.6.9 versions seem to be affected.