Please read this message in its entirely and take the recommended actions.
On February 9, we notified you of a security vulnerability in some older versions of Parallels Plesk Panel (see below). In that notification, we recommended updating to one of several versions of Plesk where this vulnerability had already been patched. We sent a reminder e-mail on February 21.
This notification is just another reminder. If you have already applied the recommended update or were already running an up-to-date version, no further action is required.
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Please follow our Knowledge Base article for instructions to install these patches:
http://kb.parallels.com/en/113321