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本帖最后由 av88xyz 于 2019-5-22 22:53 编辑
一个程序下载下来,我用百度在线查杀了下,说是有后门这个文件php,麻烦看下解释下这个可以做什么,谢谢大佬
session_start();//首先要启动session
header('Content-type:image/jpeg');
$width=120;
$height=40;
$element=array('a','b','c','d','e','f','g','h','i','j','k','m','n','o','p','q','r','s','t','u','v','w','x','y','z');
$string='';
for ($i=0;$i<4;$i++){
$string.=$element[rand(0,count($element)-1)];
}
$img=imagecreatetruecolor($width, $height);
$colorBg=imagecolorallocate($img,rand(200,255),rand(200,255),rand(200,255));
$colorBorder=imagecolorallocate($img,rand(200,255),rand(200,255),rand(200,255));
$colorString=imagecolorallocate($img,rand(10,100),rand(10,100),rand(10,100));
imagefill($img,0,0,$colorBg);
imagerectangle($img,0,0,$width-1,$height-1,$colorBorder);
for($i=0;$i<100;$i++){
imagesetpixel($img,rand(0,$width-1),rand(0,$height-1),imagecolorallocate($img,rand(100,200),rand(100,200),rand(100,200)));
}
for($i=0;$i<3;$i++){
imageline($img,rand(0,$width/2),rand(0,$height),rand($width/2,$width),rand(0,$height),imagecolorallocate($img,rand(100,200),rand(100,200),rand(100,200)));
}
//imagestring($img,5,0,0,$string,$colorString);
$_SESSION['yzm'] = $string;
imagettftext($img,45,rand(-5,5),rand(5,15),rand(30,35),$colorString,'font/PSL153.ttf',$string);
imagejpeg($img);
imagedestroy($img); |
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