[Plugin: AntiVirus] is it a hack?

found datauri.php file in theams/my_theam/images of this content – is it a hack?

<?php
$input=$_GET['in'];

?>Generated for
<?php
echo $input.'';
$ext=explode('.', $input);
?>
background:url(data:image/<?php
echo $ext[1];
?>;base64,<?php
echo base64_encode(file_get_contents($input));
?>) no-repeat left center;

[Moderator Note: Please post code or markup snippets between backticks or use the code button.]

Thank you for your efforts.

http://wordpress.org/extend/plugins/antivirus/