Monday, January 20, 2014

Fuzzing vulnserver with Python

A request from the corelan.be forums was made asking about creating a custom fuzzer using Python. It's simple enough, but for posterity let's go through this process.

Fuzzing

So, if we examined the kinds of input Peach was supplying to vulnserver when we fuzzed the HTER command in a previous post we see that it basically threw a bunch of junk input of varying sizes. In a very bad generalization, it's increasing the amount of junk to determine if it crashes the program. Fuzzing is a lot more complicated and nuanced than this obviously so check out this book or these links for further reading. 

Using Python to Fuzz

OK, but lets try and roll our own fuzzer in Python for the HTER command. If we recall the StateModel we created in our Peach Pit, the format of the HTER protocol was:
  1. Receive some data
  2. Send the HTER command with our input
  3. Receive some data

With this in mind, we know enough to go about creating our fuzzer in Python. The general flow is going to be:
  1. Create a connection to vulnserver
  2. Receive the banner for vulnserver, i.e. "Welcome to Vulnerable Server..."
  3. Send our fuzzed data in ever increasing amounts, i.e. "HTER <fuzzed input>
  4. Receive the response from vulnserver, i.e. "HTER RUNNING FINE"
  5. Increase the amount of fuzzed input
  6. Close the connection to vulnerserver
  7. Go back to step 1
  8. If we can't connect to vulnserver then we can guess that the previous input crashed vulnserver and we can print a message
Here's what this looks like in code:

Here's what the output looks like when running this script against an instance of vulnserver:

And we are greeted with this popup as well:

So we have a good indication that 2040 As will result in vulnserver crashing. Let's make a quick proof of concept from our fuzzer to test if 2040 As will crash vulnserver.

Not that complicated, but when we run it we get the popup that vulnserver.exe has crashed so we're on to something.

Viewing the Crash Under a Debugger

Just for fun, let's run vulnserver under Immunity Debugger and see what's going on under the covers when we run our proof of concept. You can get Immunity Debugger from here.
First we'll start Immunity. Then File > Open and select vulnserver.exe and then click the Open button. This spin up vulnserver, but pause it right before it hits the Program entry point. You should see on the bottom right hand side a yellow text box that says "Paused". Hit F9 or go to Debug > Run to start the program. That yellow text box saying "Paused" should now say "Running". Great, now we have vulnserver up and running so we can throw our proof of concept at it. Hopefully we should see some registers light up with As when we run it.
Once we execute our proof of concept we see at the bottom of Immunity that we've hit an exception.

And if we look at our registers we see that this particular crash didn't reveal anything too interesting.

It looks like we were able to overwrite most of EBP, but we didn't get a hold of anything else =/. Ohh well, from here we could start throwing 2030 As and so on to see if we get a better result.

Hope this helped.

33 comments:

  1. Replies
    1. CRYPTO ACCOUNT TAKEOVER (ATO) FAKE INVESTMENT & OTHER TROUBLESHOOT. As Bitcoin reaches all-time highs, and continues to go through price action swings, it has been attracting a lot of attention. As unknowing, new supporters of Bitcoin enter the cryptocurrency craze, this has presented ideal opportunities for Bitcoin scams to occur. Every day investors are getting scammed by old and new tactics. It’s important to note that although Bitcoin itself is not a scam, attacks are on the rise and they are costing individuals, businesses, and organizations significant financial and damage that are often difficult to recover quickly. When it comes to Binary Options, there are quite people who have been taken for a ride by a Brokers and at a result of this many have lost a large amount of money to Fake Binary Option Scammers this bring Investors down to a Zero point financially.

      D-hackers is a multinational equipped Hackers come together as a team to track down & to recover whatever that has being stolen from you from the most difficult internet SCAMMERS. NOTE!! We've received countless heartbreaking reports of notorious cyber scammers and we’ve successful recover them back.

      contact us on
      1⃣Binary Recovery.
      2⃣Files Recovery
      3⃣School Grades Change & Exam Questions
      4⃣Password Bypass / Recovery
      5⃣Malware Removal / Criminal Record Expunge
      6⃣Blank ATM Card
      7⃣Social Media Hack
      8⃣Remote Mobile Monitoring & Hacking
      9⃣ Credit Repair
      ­čöčPrivate Key Reset

      Relate whatever it is to City Center Of Binary Option Service & allow us give you positive result with our hacking skills. Visit our BLOG page Dhackerspot.com
      Email ­čôę binaryoptionservice01@gmail.com pointekhack@gmail.com cyberhackertap@gmail.com we Guarantee you up to %85
      REMEMBER YOUR HAPPINESS

      Delete
    2. DR. JOROMI IS TRULY A POWERFUL MAN. Contacting Dr Joromi is the best thing that has ever happened to me. My husband left me for another woman for the reason which i know nothing about. I tried every means to get him back but to no avail, all my efforts proved abortive. I was even contemplating suicide. On a lucky day when i was browsing the internet, i came across some amazing testimonies about Dr. Joromi on how he has helped a lot of people with his powerful love spells. I contacted him and explained all my problems to him and he assured me that he will help me. He told me what to do and assured me that my man will be back in 12 hours. I obeyed him and followed the instructions and to my Greatest surprise, my man called me in 12 hours time just as Dr. Joromi said. Thank you Dr Joromi. May the good God continue to bless you. If you are in need of help please contact Dr Joromi now on his website: https://www.joromispells.com and you can also reach him with his email: Joromispells@gmail.com and here is his WhatsApp number which you can also use to reach him +2348138695387 Thank you Dr Joromi. Thank you once again

      Delete
  2. I like this site for it's comprehensive and extensive information best for programmers and or students. Thank you for sharing.

    ReplyDelete
  3. Good Post! Thank you so much for sharing this pretty post, it was so good to read and useful to improve my knowledge as updated one, keep blogging.
    appvn
    hotmail sign up login

    ReplyDelete
  4. I faced a lot of problems with this. Fortunately, I have a friend who helped me with it. I think, I need to learn more about it.

    ReplyDelete

  5. I really enjoy reading of your article. I wanted to inform you that you have people like me who appreciate your work.

    techwithgeeks
    talesbuzz
    whizzherald

    ReplyDelete
  6. Confront your cheating spouse with evidence, i was able to spy on my cheating ex phone without finding out.....it really helped me during my divorce ...you can contact BESTAPPSHACKERS@GMAIL.COM) call and text him whatsapp +1(602) 609-4730 for spying and hacking social networks, school servers, icloud and much more, viber chats hack, Facebook messages and yahoo messenger, calls log and spy call recording, monitoring SMS text messages remotely, cell phone GPS location tracking, spy on Whats app Messages, his services are AFFORDABLE .............179800

    ReplyDelete
  7. If you are looking for a professional hacker to provide hacking solutions on

    -Social media hacks

    -Recovering Scammed funds

    -Email hacks

    -Phone hacks

    -DMV database

    -School result upgrading

    -Tracking & Finding People

    -Increased Credit score boost to 850

    - Access your spouse/partner social media, Monitor your colleague

    -Bitcoin mining, Lost Forex trading funds recovery, Lost Cryptocurrency trading funds recovery, Binary option funds recovery and a lot more, search no further.

    -Hunting Down Scammers With the help of, Federal Bureau of Investigation (FBI) and The International Criminal Police Organisation (INTERPOL)✅

    I fully recommend it to everyone, he recovered all data I had on a lost phone and helped in tracking the phone till it was found. I feel so happy writing this review about him, try him he's the best.

    Email. info@wizardcharlesgrouphackers.com

    visit their website to read more about them: https://wizardcharlesgrouphackers.com/.n/

    ReplyDelete
  8. I am Leah Hart I live in Ohio USA I’m 32 Years old, am so happy I got my blank ATM card from united hacking company  blank ATM card that can withdraw $5,500 daily. I got it from him  last week and now I have withdrawn about $15,000 for free. The blank ATM withdraws money from any ATM machines and there is no name on it because it is blank just your PIN will be on it, it is not traceable and now I have money for business, shopping and enough money for me and my family to live on.I am really glad and happy i met united hacking company  because I met Five persons before him and they could not help me. But am happy now united hacking company  sent the card through DHL and I got it in two days. Get your own card from him right now, he is giving it out for small fee to help people even if it is illegal but it helps a lot and no one ever gets caught or traced. I’m happy and grateful to the united hacking company   because he changed my story all of a sudden. The card works in all countries that is the good news contact. email address: unitedblankatmhackcard@gmail.com 

    ReplyDelete
  9. Finally I have been able to retrieve all my lost funds of about $35,000,which I never believed I would get again from 24options,they stocked my trading capital for over 3 months now, and denied me access to my trading account. I’m so glad that I have gotten back all my funds back without stress, All thanks to my neighbor who introduced me to a certified binary option recovery expert. Do you have funds that you wish to withdraw from your account, is your Broker manager asking you to make more deposit before you can place a withdrawal, have you lost money from any investment online? , are you confused and you don’t know how to go about ? Contact (liamsophia39@gmail.com) and also on Whats-app +1 (814)503-0528

    ReplyDelete
  10. INSTEAD OF BITCOIN INVESTMENT SCAM WHY DON'T YOU CONTACT MR OSCAR FOR A REAL BLANK ATM CARD
    oscarwhitehackersworld@gmail.com or whats-app +1(513)-299-8247.


    My name is Morgan Williams am from Alabama United State,this is so real and wonderful, at first i thought is a scam , because have been scam by several people claiming they can help me invest my money in bitcoin trading , that is how i lost my $25,000 last week on investment , but with the help of Mr Oscar White Blank ATM Card oscarwhitehackersworld@gmail.com , i was able to withdraw $50,000 from ATM machine without trace more than the money i lost last week , indeed Mr Oscar your Blank ATM card is real and genuine , i will keep telling people about you as i promise to do , if you are in any financial problem to pay up bills and start up a new life , kindly contact Mr Oscar white on how you can obtain his Blank ATM card , he does not charge big , trust him and contact him today through email oscarwhitehackersworld@gmail.com or whats-app +1(513)-299-8247.

    ReplyDelete
  11. It’s really a cool and useful piece of info.

    ReplyDelete
  12. I just have to introduce this hacker that I have been working with him on getting my credit score been boosted across the Equifax, TransUnion and Experian report. He made a lot of good changes on my credit report by erasing all the past eviction, bad collections and DUI off my credit report history and also increased my FICO score above 876 across my three credit bureaus report. Email him here via Email him here via hackintechnology@cyberservices.com or whatsapp Number: 213 295 1376.

    ReplyDelete
  13. I promised I was going to post a review about them & well i have always used these guys for RELIABLE PRIVATE ONLINE INVESTIGATIONS Have you ever needed an expert when it comes to hacking? Have you ever wanted to hack someone’s email account? Recover lost accounts,school grade,boost credit score? Do you need to find a person’s sensitive information? Do you want to invade a person’s PayPal, Skrill, Amazon, Facebook or any other site account? Upgrade of University Grades,Password and email Retrieval, phone Lines monitoring, Skype Accounts, Hack Social Network, Trace calls on real time conversations, Remove Criminal Records, Credit Fixing, cyber-crime investigation, Hack Bank Accounts, Identification of Cheating Partner or employee,Then contact Mr Ross King;
    Email / Hangout:- stocktipsandethicalhacking2020@gmail.com
    Telegram / Business Whatsapp :- ‪ +1 (925) 291-0054‬) or click on this link to chat on whatsapp https://wa.me/message/REE2BBXU4CEYF1

    ReplyDelete
  14. Never met any hacker as discreet and fast like this Best System Hackers. They are called Best System Hacks and they has helped me in multiple ways first was when my ex spouse cheated on me- they got me every information from my spouse phone number and now they are helping me paying my credit cards debts. They have the best hacking tools plus service any one can ever imagine and I recommend him to the world. I am thankful and grateful for the second chance. Honestly, Best System hackers are life savers please contact them here if you need their swift service Email; BESTSYSTEMHACKSOLUTION@GMAIL.COM or text him on WhatsApp +1 (602) 609-4730 he is very trustworthy.

    ReplyDelete
  15. Instant Money Spells Without Ingredients +27735257866 in South Africa,USA,UK,Canada,Lesotho,Zambia,Zimbabwe,UAE,Kenya,Austria,Australia,Botswana,Malta,Brunei,France,Sweden,Denmark, Belgium,Hong Kong,Russia,Brazil,New Zealand,Switzerland,Swaziland,Norway,Netherlands,Lithuania,German,Chile,Argentina,Belarus,Poland,Korea,,DRC,Fiji,Italy,Spain,Wales,Bahamas,Taiwan,Indonesia,Singapore,Czech Republic,Serbia,Palau,Malaysia,Kuwait,South Korea,Algeria,Morocco,Tunisia,Libya,Sudan,China,Hong Kong,Myanmar.. Get Money spells that will increase your wealth, money spells to help you get more money and money spells to solve all your financial problems. I have access to the supernatural world & can use my divination powers to change your money fortunes and set you to a path of bountifulness and no lack. Be financially secure happy and deliciously rich with all the material wealth that money can buy with my money spells. Email sheikhmbuga5@gmail.com OR Contact maamarazaq +27735257866 https://maamarazaq.doodlekit.com http://bestlovespells.over-blog.com https://mamarazaq.blogspot.com https://maamarazaqspellscaster.podbean.com

    ReplyDelete
  16. Instant Spiritual Working Money Spells +27735257866 in South Africa,USA,UK,Canada,Lesotho,Zambia,Zimbabwe,UAE,Kenya,Austria,Australia,Botswana,Malta,Brunei,France,Sweden,Denmark, Belgium,Hong Kong,Russia,Brazil,New Zealand,Switzerland,Swaziland,Norway,Netherlands,Lithuania,German,Chile,Argentina,Belarus,Poland,Korea,DRC,Fiji,Italy,Spain,Wales,Bahamas,Taiwan,Indonesia,Singapore,Czech Republic,Serbia,Palau,Malaysia,Kuwait,South Korea,Algeria,Morocco,Tunisia,Libya,Sudan,China,Hong Kong,Myanmar...You need money and you need it now. There are bills to pay, things you want in life. This powerful money spell can bring them to you. Tired of having to wait because you have bills to pay and no money to do it? This no debt, more money spell is powerful enough to influence your financial freedom. Email sheikhmbuga5@gmail.com OR Contact maamarazaq +27735257866 https://maamarazaq.doodlekit.com http://bestlovespells.over-blog.com https://mamarazaq.blogspot.com https://maamarazaqspellscaster.podbean.com Want to be able to live the life you want? Not be restricted by money? Using powerful money spells has significant increase in the stimulus around you to attract more money. You want this spell so you can stop worrying about having nothing in the bank. Many have used this to gain their financial edge.

    ReplyDelete
  17. Effective Lost Love Spells Caster +27735257866 in South Africa,UK,USA,Spain,Sweden,Canada,UAE,Malta,Brunei,Japan,Ireland,Turkey,Luxembourg,Iceland,Norway,Australia,Qatar,Croatia,Austria,Denmark,Netherlands,Romania,Belgium,Greece,Belarus,New Zealand,Switzerland,Cyprus,Poland,Estonia,Egypt,Fiji,Wales,Bahamas,Taiwan,Indonesia,Singapore,Czech Republic,Serbia,Palau,Lithuania,Malaysia,France,Bulgaria,German,Jordan,Chile,Algeria,Zambia,Zimbabwe,Botswana,Lesotho,Italy,Philippines,Honduras,Finland,Hungary,Mexico,Macedonia,Argentina,Syria,China,Hong Kong,Myanmar,Kuwait,South Korea,Morocco,Tunisia,Libya,Sudan,San Marino,Israel.. Witchcraft Love Spells are among the most powerful love spells ever known on the earth. I am honest, and I genuinely care for all the clients who choose me to cast a spell for them. Enhance your life, relationships, business and abilities using traditional muthi & traditional spell casting that may help make your desires come true. This is the right place where you can acquire the most potent and authentic spiritual help, Am a powerful Spell Caster with powerful love spells, to help Fix marriage problems, financial problems, court cases, business success and reuniting lovers. Contact maamarazaq 24/7 call or Whatsapp +27735257866 or Email:sheikhmbuga5@gmail.com https://maamarazaq.doodlekit.com http://bestlovespells.over-blog.com https://mamarazaq.blogspot.com https://maamarazaqspellscaster.podbean.com

    ReplyDelete
  18. Guaranteed Love Spells that works +27735257866 in South Africa,UK,USA,Spain,Sweden,Canada,UAE,Malta,Brunei,Japan,Ireland,Turkey,Luxembourg,Iceland,Norway,Australia,Qatar,Croatia,Austria,Denmark,Netherlands,Romania,Belgium,Greece,Belarus,New Zealand,Switzerland,Cyprus,Poland,Estonia,Egypt,Fiji,Wales,Bahamas,Taiwan,Indonesia,Singapore,Czech Republic,Serbia,Palau,Lithuania,Malaysia,France,Bulgaria,German,Jordan,Chile,Algeria,Zambia,Zimbabwe,Botswana,Lesotho,Italy,Philippines,Honduras,Finland,Hungary,Mexico,Macedonia,Argentina,Syria,China,Hong Kong,Myanmar,Kuwait,South Korea,Morocco,Tunisia,Libya,Sudan,San Marino,Israel.. Spells are sometimes spoken on the image or sculpture of the focused person as sometimes written on a special piece of paper of on red candles depending upon the intensity of your issue and purity of your love and thoughts. Contact +27735257866 (Call/WhatsApp) OR Email:sheikhmbuga5@gmail.com https://maamarazaq.doodlekit.com http://bestlovespells.over-blog.com https://mamarazaq.blogspot.com https://maamarazaqspellscaster.podbean.com . Few people think that for love spells to really work some rhyming chants must be memorized; it is not true, because knowing only a few special words or lines told by the magician is sufficient. The most important matter is your imagination, in which you feel your lover in front of you, moreover, for more powerful perceptions your lover may be felt physically with you that you are holding him/her in your arms. Then speaking the spells does matter, because now your spell words would generate powerful positive energy to impress your lover’s soul to attract towards you.

    ReplyDelete
  19. Love Spells to return lost lover in 2 days +27735257866 in South Africa,UK,USA,Spain,Sweden,Canada,UAE,Malta,Brunei,Japan,Ireland,Turkey,Luxembourg,Iceland,Norway,Australia,Qatar,Croatia,Austria,Denmark,Netherlands,Romania,Belgium,Greece,Belarus,New Zealand,Switzerland,Cyprus,Poland,Estonia,Egypt,Fiji,Wales,Bahamas,Taiwan,Indonesia,Singapore,Czech Republic,Serbia,Palau,Lithuania,Malaysia,France,Bulgaria,German,Jordan,Chile,Algeria,Zambia,Zimbabwe,Botswana,Lesotho,Italy,Philippines,Honduras,Finland,Hungary,Mexico,Macedonia,Argentina,Syria,China,Hong Kong,Myanmar,Kuwait,South Korea,Morocco,Tunisia,Libya,Sudan,San Marino,Israel... Is there anyone you wish to fall in love with but worried they might reject you? Are you failing to get your crush to be your true partner And pay Lobola for you? Have you been casting spells to make someone love you but that did not work for you? Have you lost faith in love because of the scammers that failed to cast you real spells? Well, I’m here to retain your faith. It’s not yet lost and don't lose hope. Get Married with my happy Marriage Spells, Return Your Lost Lover in just 2 DAYS even when gone for long time. These spells have built many relationships and yours WILL be the next one. Stop Barrenness (have children).Do not end up being in a relationship with someone you don’t love just because your true crush is not interested. Call for mama's Love Spells now....Call +27735257866 (Call/WhatsApp) OR Email:sheikhmbuga5@gmail.com https://maamarazaq.doodlekit.com http://bestlovespells.over-blog.com https://mamarazaq.blogspot.com https://maamarazaqspellscaster.podbean.com

    ReplyDelete
  20. Most Powerful Love Spells Caster +27735257866 in South Africa,UK,USA,Spain,Sweden,Canada,UAE,Malta,Brunei,Japan,Ireland,Turkey,Luxembourg,Iceland,Norway,Australia,Qatar,Croatia,Austria,Denmark,Netherlands,Romania,Belgium,Greece,Belarus,New Zealand,Switzerland,Cyprus,Poland,Estonia,Egypt,Fiji,Wales,Bahamas,Taiwan,Indonesia,Singapore,Czech Republic,Serbia,Palau,Lithuania,Malaysia,France,Bulgaria,German,Jordan,Chile,Algeria,Zambia,Zimbabwe,Botswana,Lesotho,Italy,Philippines,Honduras,Finland,Hungary,Mexico,Macedonia,Argentina,Syria,China,Hong Kong,Myanmar,Kuwait,South Korea,Morocco,Tunisia,Libya,Sudan,San Marino,Israel.. Contact +27735257866 (Call/WhatsApp) OR Email:sheikhmbuga5@gmail.com https://maamarazaq.doodlekit.com http://bestlovespells.over-blog.com https://mamarazaq.blogspot.com https://maamarazaqspellscaster.podbean.com Maamarazaq a gifted spiritual healer and spells caster who may sort your issues and problems.“I Cast spells”. With the help my spiritual powers, my spell casting is done in a unique way to help in your problems. If you have been disappointed by other spell casters and healers who have failed to provide you with the results they promised you and you’re stuck with no option of happiness. It’s never too late for your problems to be solved, it’s time to have a change in life for the better and don’t just sit back and think your worst situation cannot be changed for better because GOD helps those who help themselves,could submit to me your details I may be in position to help you out. 1) DO YOU HAVE A PROBLEM IN YOUR LOVE, IS IT DETERIORATING? I think your partner is no longer interested in you. -You might think that there is no other solution. I offer solutions for all love related problems. I could strengthen bonds in all love relationships and marriage.
    1) DO YOU WANT AN EVERLASTING LOVE WITH YOUR PARTNER?
    2) I may restore love and happiness when relationships break up or down.
    3) I may bring back your lost love.
    4) I may help you look and choose for the best suitable partner when you can’t break the cycle of loneliness.
    5) I may help to keep your partner faithful and be loyal to you alone.
    6) I may create an everlasting love between couples.

    ReplyDelete
  21. If You Are Trying To Catch Your Cheating Spouse In The Act, I Strongly Recommend You Contact This Awesome Hacker That Helped Me Monitor My Husband’s Phone When I Was Gathering Evidence During The Divorce. I Got Virtually Every Information She Has Been Hiding Over The Months Easily On My Own Phone: The Spy App Diverted All Her Whatsapp, Facebook, Text Messages, Sent And Received Through The Phone: I Also Got Her Phone Calls And Deleted Messages. She Could Not Believe Her Eyes When She Saw The Evidence Because She Had No Idea She Was Hacked, I Didn’t Need To Touch Her Phone At all,.I Certainly Recommend Contact: “WhitehatstechAtgmailDotcom ”

    ReplyDelete
  22. This type of message always inspiring and I prefer to read quality content, So happy to find good place to many here in the post, the writing is just great, thanks for the post.
    website

    ReplyDelete
  23. Knowit ERP offers solutions across various industries like steel Tube and Pipe industry ,Metal Fabrication industry. We provide the best erp software for steel manufacturing company in India.
    ERP for hot rolling
    erp for steel bars industry
    erp for manufacturing industry in india
    sheet metal fabrication software

    ReplyDelete