参考网页

https://blog.csdn.net/m0_38032942/article/details/80068949

https://bbs.csdn.net/topics/392349427

作法

<img src="" onerror='setTimeout(function(){if(top!==self){window.top.location.href=window.location.href}if(!/(csdn.net|iteye.com|baiducontent.com|googleusercontent.com|360webcache.com|sogoucdn.com|bingj.com)$/.test(window.location.hostname)){window.location.href="\x68\x74\x74\x70\x73\x3a\x2f\x2f\x77\x77\x77\x2e\x63\x73\x64\x6e\x2e\x6e\x65\x74"}},3000);'>
 

使用notepad或者其余工具打开外边那个网页，Ctrl F 查找 noerror ，将那一行删除便可

 

csdn反人性设计，只能呵呵了