A few days ago in all versions of Joomla (1.5, 2.5, 3) found critical (0-day) vulnerability that allows an attacker to successfully attack the sites running Joomla absolutely all versions of the Exploitation of the vulnerability of RCE ("remote code execution") and, as a result, to gain complete control over the site. The attack is made possible due to insufficient filtering of variables in the HTTP request (the field HTTP_USER_AGENT, HTTP_X_FORWARDED_FOR, REMOTE_ADDR) and their subsequent use in the session object, and query a database.

September 30, 2014 it became known about the vulnerability in the software company Akeeba. The vulnerability allows remote upload shell, with no rights in the system. Are affected as the products themselves Akeeba: Akeeba Backup, Akeeba Solo, Akeeba CMS Update, Akeeba Admin Tools, and WARNING: all versions of Joomla 2.5 to version 2.5.27, and 3 to version 3.3.5.

The fact that the standard Joomla component updates using scripts of Akeeba. And Akeeba Joomla and released their updates, covering this vulnerability, but they did not consider it a critical vulnerability, and so many people do not pay much attention to it.

Indeed, a hacker could exploit this vulnerability only when you make a backup copy of your site, or are upgrading the site. That is, it is only a few seconds of which the hacker must still somehow and learn.

Of such an attack, we have already written, but in recent days they have intensified with incredible force. The essence of the attack is that the bots of passwords to the admin panel of the website. It is dangerous not only because the password sooner or later they still can pick up, but the fact that it was created a pretty decent load on the server.

Since the attacks in recent days have purchased just incredible strength, the server hosts many simply can not withstand such loads exorbitant. Hosters naturally try to cope with this scourge, but it is they do not always work, as the number of bots is huge and firewalls can not cope with so many locks. Therefore, some of them, as a temporary solution to block requests for files wp-login.php to wordpress and administrator / index.php for Joomla.

August 1, 2013 came the critical updates for Joomla second and third versions. Vulnerability affects all previous versions, ie version 2.5.13 and earlier line 2.5.x, and version 3.1.4 and earlier line 3.x.

Most likely vulnerabilities are also prone version 1.6.x and 1.7.x

Vulnerability is the ability to download file an unauthorized user, which will inevitably will lead to the breaking of your site.