Weird code in index.php - \x01\x00\x01\x00\

[PLAYBOY]

I have the below code in my index.php and since these kinda codes are usually spam or malicious codes I just wanna ask to see if you guys know anything about this code?

Code Select Expand

// The main controlling function.
function smf_main()
{
global $modSettings, $settings, $user_info, $board, $topic, $board_info, $maintenance, $sourcedir;

// Special case: session keep-alive, output a transparent pixel.
if (isset($_GET['action']) && $_GET['action'] == 'keepalive')
{
header('Content-Type: image/gif');
die("\x47\x49\x46\x38\x39\x61\x01\x00\x01\x00\x80\x00\x00\x00\x00\x00\x00\x00\x00\x21\xF9\x04\x01\x00\x00\x00\x00\x2C\x00\x00\x00\x00\x01\x00\x01\x00\x00\x02\x02\x44\x01\x00\x3B");
}

// Load the user's cookie (or set as guest) and load their settings.
loadUserSettings();



I`m worried especially about this part
"\x47\x49\x46\x38\x39\x61\x01\x00\x01\x00\x80\x00\x00\x00\x00\x00\x00\x00\x00\x21\xF9\x04\x01\x00\x00\x00\x00\x2C\x00\x00\x00\x00\x01\x00\x01\x00\x00\x02\x02\x44\x01\x00\x3B")

[JBlaze]

Code Select Expand

// Special case: session keep-alive, output a transparent pixel.

It's part of SMF code, and it's doing exactly as the comment suggests. It outputs a 1x1 transparent pixel.

Nothing to worry about