forensics ctf writeups

However, this returned Filename has an unknown suffix, skipping, so I renamed it to flag2.lzma and I extracted it using. The Forensics challenges I solved in picoCTF 2022 are the following. So I looked up 17d62de1495d4404f6fb385bdfd7ead5c897ea22 on Google, and saw that it corresponded to Awakened.2013.1080p.BluRay.X264-iNVANDRAREN. Similar to the first task, binwalk the oreo.jpg. DEV Community 2016 - 2022. As for this kind of challenges i use autopsy ! Some people thought that Truecrypt had hidden vulnerabilities but long history short, nothing was found. i opened the image and while its scaning it was there some really juicy information we can notice in the results section . This created a file called flag2.out, and revealed that it was a LZMA compressed data. This is crucial because if the container was not mounted we weren't able to retrieve the keys for opening it. I decrypted it using what was mentioned in the conversation, openssl des3 -d -salt -in saltedfile.bin -out file.txt -k supersecretpassword123. Here, I saw that the pin 40000000 took the longest, with a significant time difference from the other PINs. GreHack CTF 2022. game reverse network proxy. At the 2021 census its population . So lets open the container, using Veracrypt we can open it. The third byte is "delta Y", with down (toward the user) being negative. Save. Zh3r0 CTF : Digital Forensics Writeups. The extracted folder contained a file called flag. I tried to open this up in my PDF reader, but it said that it cannot be opened. GreHack CTF 2022. programming proxy network. Last week a CTF event organized by the Spanish Guardia Civil was organized, the II NATIONAL CYBERLEAGUE GC. I decided to look further into this, so I took the offset for nano flag.txt, which is 204193835, and subtracted 184549376 (which is 360448 * 512) using. so this time we try to search what the reports can give us ! Knowing the operative system we can start to extract useful information. Moreover, this replicates a real scenario. The overall packet capture looks like the following. This created a file called flag2, and revealed that it was a LZOP compressed data. Located in the northern part of the country, it is the administrative centre of Pleven Province, as well as of the subordinate Pleven municipality. $ strings -t d disk.flag.img | grep -iE "flag.uni.txt". As hash is 68 61 73 68 in hex, I inputted this hex value into the Wireshark search to look for all packets that contained this hash information. I checked the file type of 64, and revealed that it was a gzip compressed data. The suggested profiles are Windows XP related, we can use one of them WinXPSP2x86 or WinXPSP3x86. 3. However, there were too many entries with the string flag, so I decided to narrow the string search down. I downloaded the file, extracted it. 1. The flag is hidden inside the I warned you.jpg file. flag : zh3r0{C:\Users\zh3r0\Documents\Hades.exe}, Chall name : Run Forrest RunChall description : Just like one other malware you found, we found traces of another malware which is able to start itself without user intervention, but this time we have no idea or info on when it starts or what triggers it, we only know that it runs automatically! And we need answers to some questions that follow, this would be your first assignment! We hosted our first CTF successfully. I looked through a few more, and I was at packet 51080 which had a hash value of e2467cbf021192c241367b892230dc1e05c0580e. Executing this showed that 48390513 is the correct PIN. We are also given the file capture.flag.pcap. As this is a torrent challenge, I went to Wireshark and enabled the BitTorrent DHT Protocol (BT-DHT) by going to Analyze -> Enabled Protocol. Another image is extracted from the zip. Unflagging lambdamamba will restore default visibility to their posts. By just opening the first report i think we can determine after some analysis we found the flag, Software\Microsoft\Windows\CurrentVersion\Explorer\Shell FoldersLastWrite Time Sun Jun 14 10:03:02 2020 (UTC). note : please read every line because its necessary to understand whats going on and how i thought threw the challs ! And this revealed that it was a shell archive text. As for today, we are going to walk through the Medium level forensics. while browsing the file i noticed a folder called typedurls , that was really worth checking because we see in autopsy there was a web history result section but not the full one , so after scaning this file we found a url that looks really suspecious http://w3.you-got-million-dollars-click-me.nr.hg.org.tech/ ( please dont enter it nthng there ) so we wrapp the url with the flag format and boom we get the flag, flag : zh3r0{http://w3.you-got-million-dollars-click-me.nr.hg.org.tech/}. Having a RAM acquisition can give us a lot of information in a digital forensics investigation. If lambdamamba is not suspended, they can still re-publish their posts from their dashboard. This will let us know whats processes were running in the system. This file corresponded to name: Zoo (2017) 720p WEB-DL x264 ESubs - MkvHub.Com. From this, I assumed that the flag was first written into flag.txt, encrypted and put into flag.txt.enc using OpenSSL aes256 with the salt option and a password with unbreakablepassword1234567, and flag.txt was shredded. Badsud0 Capture the flag team leader ,TUN. Let's do a quick start. We solved all the digital forensics . We are also given the file anthem.flag.txt. The flag is hidden on the second commit. Binary Exploitation (Solved 5/14) 4. So by a little brainstorming analyse we have : he loves what he does (math) // how this man can live xD, he have some enemies in the company he works in. We are also given the file disk.flag.img.gz. while i was searching arround i reports and documents i was taking some notes about what could be malicious , and this where things get intersting by side ! Bachelor of Computer Science and MSc on Cyber Security. Lets do a quick start. After unlocking we got a image which have the flag . using the same in these challenge we are getting asked to search for some several vectors that the malware could get into from ! This shows that 48390510 takes the longest, therefore I will be using this for the eighth test batch. Cryptography (Solved 11/15) I made the following Python script side.py to measure the time before Access denied. Templates let you quickly answer FAQs or store snippets for re-use. Hi all , I participated at zh3r0 ctf with my team and we finished up 7th in the ctf , there was really cool challenges . well looking in all these files will take so long so why dont we find if there is something that clue us about the file . I will find the intended solution and update the post soon. The first thing we did was to open up the WAV file and check out the content. so i saw xxd of the file . so by entering the files of the system we play arround in somefiles until we stamp by a file name called TimeZonesInformation and with it were pleased with the author name : Cicada3310. Xor the extracted image with the distorted image with stegsolve. Chall name : SoundlessChall description : Good job in finding the flag! On downloading the resources we get a image and wav files So from description it is clear that we need to do so using aperies.fr I got the key and on decoding the wave file as it was a morse code : So it was clear nothing in audio so I use the extracted key 42845193 to extract data from steghide you can use any online tools also. Right now it is discontinued and has been replaced by Veracrypt. Cybertalents Digital Forensics CTF All Challenges Write-up. The Top 8 Cybersecurity Resources for Professionals In 2022 Nakul Singh Cyberyami CTF Graham Zemel in The Gray Area The Ultimate List of Bug Hunting Resources for Beginners HotPlugin in System Weakness Forensics Challenges HackTheBoo CTF 2022 Help Status Writers Blog Careers Privacy Terms About Text to speech I downloaded the file, extracted it, and checked the partitions using. So, I'm going to do more bundle walkthrough on the CTFLearn. as for this kind of challenges i like to discover the os version and some information about it so i played arround the files and found this under the Operating System Information section : Windows Xp service pack 1. we have an idea about what system is using so we can google about some paths that may be usefull in our challenges. With you every step of your journey. We were fortunately able to get his PCs image and some of the files in it. You can find the flag at the right place when you look, it will be obvoius when u look at it! No binwalk or steghide for this task, just a normal stereogram. Chall description : MR.Zh3r0 is a mathematician who loves what he does, he loves music and of course he is really good with personal desktops but a really gullible person who could be phished or scammed easily! I decided to view the contents of the file using. For this task, you have to look really deep. Then I used the binwalk to extract the ar archive. The first thing to do is download the memory image ( OtterCTF.vmem ). I renamed it to flag4.xz and I extracted it using. Save it as Decryptor.java and run it with the following command. This week we decided to go for HSCTF 6 organized by WW-P HSN CS Club . One of these uploads is a key and the other is a function block. Right now some systems use Hardware Security Modules for achieving that, but it is not a solved problem. FLAG. Thanks for reading. Info: NTUSER.DAT files is created for every system user which contains some personnel files and data . but after taking some time searching arround i found out that im in a rabbit hole ( that i made it by myself) . Reverse Engineering (Solved 2/12) Now the question is, find the most probable way the malware(s) couldve got in and the flag would be the name of the source. Once unpublished, this post will become invisible to the public and only accessible to Lena. which gave me this . . I went to Steganography Online to decode the image, but decoding the image did not reveal anything. So Basically autopsy gives you a report section that presents for us the recent activity that have been made in the pc . .We found that his PC had some sort of problem with Time Zones even though he tries to reset it, it seems the malware is somehow able to edit the TimeZone to what it wants, which is the malware author name. S0rry: We get a zip file protected with a password, I used zip2john to convert it to hash then cracked it with john using rockyou.txt word-list. Download the PDF file. For the first test batch, I decided to use 00000000, 10000000, 20000000, 30000000, 40000000, 50000000, 60000000, 70000000, 80000000, 90000000 for the PINs. I looked through the packets, and found the file that started with Salted in packet 57. We must subtract 4 bytes for the length field of the second IDAT, subtract 4 bytes for the CRC of the first IDAT, and subtract 4 bytes again for the chunktype of the first IDAT. $ strings -t d disk.flag.img | grep -iE "flag". Which showed the partitions and their size. I inputted this Linux partition size to the remote access checker program, which gave me the flag. We have two files from the challenge. THE hint in the challenge was asking us the re read the first chall description carefully and examining the events that occured that time . Their team did not manage to solve this challenge so lets see what was about and how to solve it. Based on the GameBoard, almost all the challenges were solved by at . This showed that the Linux partition was using a Ext4 partition with a block size of 1024 bytes. Once suspended, lambdamamba will not be able to comment or publish posts until their suspension is removed. In which, 3 were forensics category and 1 was the web category. by reaching this point we have to admit that reports section is the really usefull tool in here , its like monitoring some traffic in the network ( not exactly). As the OpenSSL with the salt option generates encrypted text that starts with Salted, I decided to string search that using, strings -t d disk.flag.img | grep -iE "Salted". while searching arround we found an exe file that seems really obvious is a thing and boom thats a flag . Is your desk photo giving away important data? Now I know what file I am supposed to look for and what directory and partition it was in. KapKan (Forensics1 . So I extracted it using. Chall description : We havent found the trace of how the virus could have got into the system. We are also given the file disk.flag.img.gz. Thanks for keeping DEV Community safe. I used the offset 114562048 and did the operations similar to Sleuthkit Apprentice to find the file contents using the commands, $ ifind -f ext4 -o 206848 -d 8453 disk.img. Either way, Volatility has some commands centred in analysing Truecrypt processed: truecryptsummary can give us information about the TrueCrypt process. The cheapest way to get from Pleven to Constana costs only $20, and the quickest way takes just 5 hours. I did the operations in Sleuthkit Apprentice to find the partition informations, and I decided to string search flag.txt using, $ strings -t d disk.flag.img | grep -iE "flag.txt". OtterCTF dates from December 2018 and includes reverse engineering, steganography, network traffic, and more traditional forensics challenges. From here it was quite frustrating because you need to guess the flag words however I cracked it. Extract all the files within the image, we find what we needed. If we open Readme.txt we can see that they are looking for the password associated with the IP: 48.37.29.153. so i looked closely and saw that so many numbers werent of 8 bytes . First off, open up the dumpster with the visualvm. So, I made the 4 challenges in zh3r0 CTF. Okay so basically I found this in 2 steps: Do keyword search for 'Anubis.exe' (include substring) It returned 4 results, and only 1 of them was a registry file. There is one password-protected zip file. How could this happen? There were files that contained OPENSSH PRIVATE KEY, so now I have to find the actual contents of the private key file. Problem is, where is the password? Just select the container, specify the password, and remember to check TrueCrypt Mode, because it is a Truecrypt container. so here basically the author tells us that the pc have an another malware so we need to find it . I went ahead to CyberChef and converted this from hex, picoCTF{f1len@m3_m@n1pul@t10n_f0r_0b2cur17y_347eae65}. Volatility is an Open Source project with a great and active community behind it, there are alternatives like Rekall but I personally prefer Volatility. the last 4 hours, we didn't well managed our time ! From the program behaviour, I saw that the length is first checked, and if the length is 8, the program proceeds to check the digits of the 8-digit PIN code (otherwise, it immediately returns Incorrect length). And I did ssh again to the remote server, which contained a file called flag.txt which contained the flag. byte 2: X movement. After realizing that i should redirect my thinking in the browser i checked what autopsy gave as information and found a NTUSER.DAT file . The password is located at the first downloaded picture where you find the mega URL. And thats all, hope you like the Write-Up ;). I assumed that this was the flag, and I just needed to add the picoCTF wrapper. For further actions, you may consider blocking this person and/or reporting abuse, Go to your customization settings to nudge your home feed to show content more relevant to your developer experience level. I checked the file type of flag, and revealed that it was a lzip compressed data. So I copied this file into a file with a .sh extension. Therefore, 40000000 is what I will be using for the second test batch, thus I used the following shell script. DEV Community A constructive and inclusive social network for software developers. I logged into the master server using this PIN, which gave me the flag. We are also given the file Flag.pdf. I tried to find the partition information using. For example, in Spain, we have a real case where the suspect used Truecrypt and it is not possible to open these containers. Rating: 4.5. We have found traces of yet another malware! Manage secrets in live memory it is a difficult and challenging process. Currently working as a cybersecurity researcher at the University of Alcal. CTFLearn write-up: Forensics (Medium) 5 minutes to read Hello there, another welcome to another CTFlearn write-up. To view some basic info about the type of memdump, we do a volatility -f memdump.raw imageinfo to view the profile. So I went to /root/my_folder directory, and I saw that flag.txt did not contain any relevant information because it was shredded. And We have a suspicion if he only downloaded one malware or more than one? Now running command in terminal. Then I used that result, 19184 to find the inode number of the file containing the string file.txt using, $ ifind -f ext4 -o 360448 -d 19184 disk.flag.img. This outputted some interesting entries, and the following caught my eye. 1) 07601 Link: https://ctflearn.com/challenge/97 This one is simple. There is the flag shown in the screenshot below. In the last few rows, I saw { 3 n h 4 n and c 3 d _ 6 7 8 3 c c 4 6 }, which looked like the flag, so I concatenated this to form {3nh4nc3d_6783cc46}. The first packet that contained info_hash was packet 79 with a hash value of 17d62de1495d4404f6fb385bdfd7ead5c897ea22. So we have just to spot where can the timezonesinfo would be . Love podcasts or audiobooks? I knew this was the file I was looking for, because OpenSSL with des3 salt will generate an encrypted file that starts with Salted. Knowing that we can launch truecryptpassphrase for retrieving the password used to open the container. Katycat Challenge (Forensics) katycat trying to find the flag but she is lazy. While reading the writeups published by CTF team bi0s, I came across the github profile of Abhiram. So I extracted it using. As most private keys contain the string OPENSSH PRIVATE KEY, I string searched that using, $ strings -t d disk.img | grep -iE "OPENSSH PRIVATE KEY". Without thinking twice, extract all the files with the following command. here , in this challenge the power of notes comes , remember when i said always take notes , well this chall didnt took more than 30 seconds . Forensics (Solved 13/13) 2. hint incase you werent able to note which is the malware name, it would be a name that is of the GOD. I applied the bt-dht filter, and looked through the packets, and saw that some contained info_hash. First of all, lets check the hidden files using the binwalk. On extracting the zip file we get two panda images at first I tried a loot of tools but it much easier the flag was in the differnce of the strings of the two images so. Our first task is to find one of the picture and XOR it to find another image. and after analysing it all , by saying analysing i mean opening it and reading it carefully because it was pretty straight we find some really good things . There are several attack vectors that a malware could get into the system which you will need to find. For solving forensics CTF challenges, the three most useful abilities are probably: Knowing a scripting language (e.g., Python) Knowing how to manipulate binary data (byte-level manipulations) in that language Recognizing formats, protocols, structures, and encodings By visiting the MEGA URL, you will get a ZIP file. So I looked into flag.uni.txt, which contained the flag. again converting the output from binary to ascii doesnt give the flag. Hello Everyone, I am a member of zh3r0 CTF team. Yaknet 3. Therefore, the PIN with the correct leftmost digit should take the longest time because it will move onto the next digit comparison. Voices in the head is a 2000 point forensic challenge. I opened up Autopsy and searched for the directory that contained flag.txt and flag.uni.txt in the fourth partition of the disk, which is Linux (0x83) 360448-614399. By checking the file type, it is a data file instead of a jpeg. Posted on Apr 3 We solved all the digital forensics challenges so were gonna make a little writeup trying to explain everything ! Since it was password protected I use fcrack and everyones fav rockyou.txt to crack it . code of conduct because it is harassing, offensive or spammy. We got another image inside 3.png. This one is simple. Like last time, it gave unknown suffix, so I renamed it to flag2.lzop, and I extracted it using. Which created a new folder called _flag.extracted, and inside was a file called 64. The flag will be in format flag{}. Solution. HTB x UNI CTF Quals Forensics Writeup. CTF Writeup: picoCTF 2022 Forensics My picoCTF 2022 writeups are broken up into the following sections, 1. Chall description : Now, that you have found out how the malware got in, the next question is to find what the malwares name is, we have got a lead though, we found out that the virus wasnt removable from the system even after a system. But I have I friend who participate, He knows I love forensic challenges so He sent me one of the challenges that were part of the competition. [Link: https://ctflearn.com/challenge/104]. I also decided to find the full contents of the file that contained Salted using, $ ifind -f ext4 -o 411648 -d 10238 disk.flag.img, $ icat -f ext4 -o 411648 disk.flag.img 1782. This CTF ran from July 7, 2017 to July 8, 2017. Use a command like strings to read the flag. So I exported the packet as saltedfile.bin using File > Export Packet Bytes. However, it had the permissions 0664 which was too open so the private key was unusable. Here is what you can do to flag lambdamamba: lambdamamba consistently posts content that violates DEV Community 's Made with love and Ruby on Rails. This shows that 48300000 takes the longest, therefore I will be using this for the fourth test batch. I used stegsolve tool to complete this challenge. Therefore, I assumed that the flag might be contained in a file named flag.txt. A collection of write-ups from the best hackers in the world on topics ranging from bug bounties and CTFs to vulnhub machines, hardware challenges and real life encounters. GreHack CTF 2022. programming proxy network. Updated on Oct 16, My picoCTF 2022 writeups are broken up into the following sections, and noticing the exe file make it clear , even for more you can google the name of exe , its not a known process or a miscrosoft one , so that makes it clearly a thing , we wrapp it into flag format and rock ! Cryptography (Solved 11/15) 3. After executing, a file called flag was generated, and checking the file type revealed that it was a current ar archive. . The flag is located at the bottom-right corner. First of all, let's check the hidden files using the binwalk. by thinking about phishing is we found that the most phishing techinques is either sending a file or a malicious url . Once unpublished, all posts by lambdamamba will become hidden and only accessible to themselves. It will become hidden in your post, but will still be visible via the comment's permalink. After renaming it .jpg I run some tools and steghide worked perfectly and I got a flag.zip file. This created a file called flag3.out, and revealed that it was a XZ compressed data. really helpfull tool (ftk imager too is a good choice). The most interesting process to lookup is TrueCrypt. Gg anyway guys ^_^ TOP15 will be qualified to the finals if their writeups were approved by the the organizers. flag : zh3r0{C:\windows\Program Files(x86)\Anubis.exe}. The information we have is that MR.Zh3r0s music folder isnt really a music folder,(i.e), hes music folder seems to trigger the virus software somehow whenever he clicks it! Most upvoted and relevant comments will be first, Cybersecurity/SOC Analyst, Global Security Camp Tutor, Security Camp Tutor, CODE BLUE Staff, GCC 2022 Taiwan Group Work Progress and Outcome. http://w3.you-got-million-dollars-click-me.nr.hg.org.tech/. name of the God huh , thats big bro x) . The first thing we need to do is to identify the operative system in order to properly analyzed the live memory adquistion. I downloaded the file, extracted it. and divided 19644459 by the block size 1024 bytes using. So I went into the webshell, and put the private key into key_file, and tried to ssh to the remote server using. Best NordVPN discount from Flicks And The City, {UPDATE} Ears Jeopardy Match Hack Free Resources Generator, The Wrap Protocol from Bender Labs is Launching: Heres What You Need to Know, Prison officer smuggled panties for prisoner, ./volatility_2.6 -f evidencias/snap.vmem imageinfo, ./volatility_2.6 -f evidencias/snap.vmem --profile WinXPSP2x86 pstree, ./volatility_2.6 -f evidencias/snap.vmem --profile WinXPSP2x86 truecryptsummary, ./volatility_2.6 -f evidencias/snap.vmem --profile WinXPSP2x86 truecryptpassphrase, ./volatility_2.6 -f evidencias/snap.vmem --profile WinXPSP2x86 truecryptmaster, we have a real case where the suspect used Truecrypt. and rest with 0 , which will give a binary and hence flag.I wrote a python file which will convert \t or 0x09 to 1 Web Exploitation (Solved 2/12), All my writeups can also be found on my GitHub's CTFwriteups repository. In this case, this is not necessary but in a real scenario where we could not be able to retrieve the master key or the password, this information is always useful. Although it hasnt been identified at a particular location, something is triggering it to restart as soon as he logs in! I double checked with Autopsy, and confirmed that the Salted file was there. enjoy ! We are also given the file torrent.pcap. We can discover processes running, dump files, secrets, connections and a lot of useful information. The first packet that contained info_hash was packet 332 with a hash value of 17c1e42e811a83f12c697c21bed9c72b5cb3000d. As for today, we will go through the easy Forensics and most of the tasks contain basic . I salute the author of this challenges it was a really nice experience being pleased with this challenges and also the ctf organizer really thank you ! Forensics (Solved 13/13) So I redirected the output to flag.txt.enc using, $ icat -f ext4 -o 411648 disk.flag.img 1782 > flag.txt.enc. I prefer to replicate and solve real scenarios in CTF challenges instead of the very strange ones. TrueCrypt was a program that allows us to created encrypted containers and partitions. Because of that, I used the latest stable release, Volatility 2.6. This created a file called flag3, and revealed that it was a LZIP compressed data. ICS A Different Type of Serial Key Attached are serial captures of two different uploads to an embedded device. However, nothing useful came up. Hello there, another welcome to another CTFlearn write-up. The most popular tool for memory analysis is Volatility. The following shows the example execution, where the Time taken is outputted in seconds. Maximum possible values are +255 to -256 (they are 9-bit quantities, two's complement). As the title suggested, the distorted image is somehow XOR between 2 pictures. I double checked with Autopsy, and saw that the commands used were contained in .ash_history. The difference is FFB1. we officially hunted down all those three malwares ! so when reranging this ideas we can have an idea that the attacker got sort kind of a malicious email that had the malware but the malware original place where ? the password is iamsorrymama ( weird password XD ), let's extract the zip file and see what we get. I did Follow TCP stream, which revealed a conversation between two people. Learn on the go with our new app. This revealed the flag at b1,rgb,lsb,xy, where rgb means it uses RGB channel, lsb means least significant bit comes first, and xy means the pixel iteration order is from left to right. Along with the challenge text and an audio file named forensic-challenge-2.wav. The password is encoded with base64 and make sure to change the URL encoded padding (%3D) to =. This will mount the container on our system giving us access to two files. well for the previous challs we just used 2 reports that have such a juicy data and we didnt have the chance to cmplete em because we were stambled by a flag ! The above image was given following the basic commands I got this by binwalk, As results show it has some RAR content on unraring the content I got the flag, As starting with the classical command to check the file formate and it was a .jpg file. $ volatility -f memdump.raw imageinfo Volatility Foundation Volatility Framework 2.6 INFO : volatility.debug : Determining profile based on KDBG search . So in this first chall were asked to give the name of the author that the malware have changed in the TimeZone information. Web Exploitation (Solved 2/12) All my writeups can also be found on my GitHub's CTFwriteups repository Hi all , I participated at zh3r0 ctf with my team and we finished up 7th in the ctf , there was really cool challenges . One is a distorted image and the other is a normal weird image. This shows that 48390500 takes the longest, therefore I will be using this for the seventh test batch. Using binwalk did not extract it, so I extracted this using. We are also given the file Financial_Report_for_ABC_Labs.pdf. Every operative system handles memory in a different way. 500. They can still re-publish the post if they are not suspended. Right now Volatility has a 3.0 version with a lot of improvements but it is under beta. How could a malware edit the TimeZone information if it had Administrator Privilege to the system!? 2. I then executed this script. so basically were provided with some files that we got from the victim pc and we need to investigate a malware that is in the victim pc . I Googled this, and saw that it corresponded to ubuntu-19.10-desktop-amd64.iso from LinuxTracker.org. Forensics Challenges. It seemed like these two people had been exchanging files, and one person forgot how to decrypt it, so the other person tells them to decrypt it using, openssl des3 -d -salt -in file.des3 -out file.txt -k supersecretpassword123. (Using strings command). I know the flag format is picoCTF{xxx}, so I decided to grep it using. always when doing things like that notes can help sometimes , maybe not now but later on . So, all credits go to this youtube video. Built on Forem the open source software that powers DEV and other inclusive communities. {UPDATE} Mouse in City Hack Free Resources Generator, Why it is important to protect your privacy online. so decided why dont we take a look back at those 2 reports ! Register for the much-awaited virtual cybersecurity conference #IWCON2022: https://iwcon.live/. Find the travel option that best suits you. FLAG : csictf{7h47_15_h0w_y0u_c4n_83c0m3_1nv151813}. The challenge only wants us to find the file name, and not reconstruct the file, so I knew that this info_hash information will be very important because it tells us the hash of the file. We are also given the file drawing.flag.svg. Reaching this point let me clarify that this is not a Truecrypt vulnerability. with some research I found that it a type of data encoding and can be solved by replacing some hex value with 1 Use git show to reveal the flag. The container seems to be an encrypted container and snap.vmem it is a RAM acquisition. As for today, we are going to walk through the Medium level forensics. This shows that 48390000 takes the longest, therefore I will be using this for the fifth test batch. Therefore, I changed the permissions to 400 using. Are you sure you want to hide this comment? The second file is a list of users and password in XML format. After that, find the passHash in the dump. I assumed that the PIN is checked from left to right, where Access denied. If you have played other CTF challenges this seems a little obvious but let it break into parts. and or 0x20 to 0.and removed remaining others . In summary, we have a password, a master key, the encryption algorithm and a container. byte 3: Y movement. At least for me, it was a fun and easy challenge. after some searching i found out that internet explorer saves some good info in this file so why dont i take look . Open up the PCAP file with Wireshark and follow the TCP stream to frame 3. We have a certain idea that somehow the virus might be redirecting the clicks to a different location where the virus resides or the location of music folder could be compltely different! From this, I assumed that the flag is contained in flag.uni.txt in the my_folder directory, so I decided to search for that using. If you find the reason or the method for the above mentioned phenomenon you will find the flag there as an obvious one. Make sure you have selected the thread. so the first idea i got is to start looking in emails and reports that autopsy grabbed for us ( man i love that tool ) . Now he cant even open his default music folder to hear some good musics! Challenge attachement link if you are interested . Opening this up on Wireshark showed the following. Using this information we could be able to start a brute force attack of the container. Much appreciated. I decided to use zsteg instead, with the -a option to try all known methods, and the -v option to run verbosely. I wanted to check if there were any strings that could hint to a flag file, so I checked for the string flag using. I assumed that the flag might be contained in a .txt file as that is the most common means of storing the flag in a disk forensics challenge. so as the description says we need to find an another malware ( those guys have no mercy for this poor man ,damn) , remember saying that reports are now our primary tool why dont we check it again and see if we missed anything . Binary Exploitation (Solved 5/14) keep pushing the image to left (press right key), you should get the flag at offset 102. Typical values for deltaX and deltaY are one or two for slow movement, and perhaps 20 for very fast movement. As you would expect, this backfired. is outputted as soon as the leftmost digit does not match. Opening this up on Wireshark showed the following, I decided to Follow TCP stream, which revealed the flag. Challenge 1 Open the registry file and look one line up. Reverse Engineering (Solved 2/12) 5. Secrets in live memory have been always a problem. Use strings command to locate the flag. To automate this process, I made the following shell script auto.sh. The challenge says to use a key_file to ssh to the remote machine, so I assumed that I need to look for a file that contained the key. were getting selected. This shows that 48390000 takes the longest, therefore I will be using this for the sixth test batch. will you help her to find the flag? Just looking for the IP will give us the password, V8M0VH. Greeting there, welcome to another CTFLearn write-up. Replace the length field with 00 00 FF A5. It contained the encrypted file with the contents. We're a place where coders share, stay up-to-date and grow their careers. Using this password we should be able to open the container but we can retrieve more info and a master key using truecryptmaster. This shows that 48000000 takes the longest, therefore I will be using this for the third test batch. I downloaded the file, extracted it, and used the following command. Extract the zip file and ignore the Loo Nothing Becomes Useless ack as it has nothing to do with the challenge. One of his HECKER friend suggested to download some virus to destroy the data the other people has. I hope you liked the CTF event. I also confirmed using Autopsy, and saw that this private key file was in /root/.ssh/id_ed25519 in the Linux partition that starts at 0000206848. We have a lot of stuff inside the image file. so i cut down all the numbers from right to 8 bytes After that, Ive drafted the following Java code. Yaknet 2. It is the biggest economic center in Northwestern Bulgaria. Subtracting 12 in total, we get FFA5. A hint was distributed to all teams as a starting point. Pleven ( Bulgarian: pronounced [plvn]) is the seventh most populous city in Bulgaria. We are also given the file network-dump.flag.pcap. 27-05-2019. This write-up only covers the memory forensics portion, but the whole CTF is available to play as of the publication of this post. I had the chance to participate with CyberErudites Team in the first edition of HackTheBox University CTF. I executed this script again to confirm. Well, it has been a while since my last walkthrough on the binary and cryptography. This is because Im not really good at Java programming. The challenge makes easiest the process of finding container but in a real scenario, you could be able to have some evidence with encrypted containers. I also checked the file system information for the Linux partition starting at 0000360448 using. Given this memory dump, we will use Volatility to proceed. The challenge asks for the Linux partition size, which is 0000202752. The following shows the example execution, where Incorrect Length is outputted when a PIN that's not 8-digits is entered, Checking PIN is outputted if a 8-digit PIN is entered, and Access denied. This created a file called flag.out, and revealed that it was a LZ4 compressed data. I made the script so that the PIN could be inputted like the following. After extracting the files, there is another oreo image (2 pieces of oreo). This returned 2363, so I printed the contents of that file using, $ icat -f ext4 -o 360448 disk.flag.img 2363. Since the flag format is picoCTF{xxx}, I decided to search for the string pico using. Before I executed this script, I closed all programs that I wasn't using to reduce variations in time due to background processes. So I extracted it using. :). and also by how i solved it so fast cuz it was written as a note thats why notes are important ! $ strings -t d disk.flag.img | grep -iE "pico". This will also give us information about the Encryption Algorithm, AES and the algorithm mode used, XTS. And we obtain the password: 13576479. This is one of the toughest challenges I faced. This CTF ran for eactly 24 hrs and we had easy, medium and hard challenges. 9 min read. Follow my twitter for latest update, If you like this post, consider a small donation. 5. This showed the full command. Author: CISA I always love to play forensics and memory analysis challenges. In this question we were given a password protected zip file so by using fcrackzip lets crack it . is outputted if the 8-digit PIN is incorrect. (Nothing Is As It Seems). We can see that the Truecrypt container was opened and mounted the 20201011. First and foremost, locate a MEGA URL inside the download image. I viewed the contents of the file, which contained a very long text. I opened the file , it was blank , but there were 88 lines which As it was encrypted using openssl aes256 -salt -in flag.txt -out flag.txt.enc -k unbreakablepassword1234567, I decrypted it using, $ openssl aes256 -d -salt -in flag.txt.enc -out flag.txt -k unbreakablepassword1234567. by scrolling down we read a ahaha thing in one of the files so we open it and start digging arround . is outputted. HSCTF 6 CTF Writeups. I always start with pstree. I saw that a directory called my_folder was created, moved into the my_folder directory, flag was written into flag.txt, flag.txt was copied into flag.uni.txt, and the original flag.txt was deleted securely using shred, which would make it extremely difficult to recover. He has called the Worlds best forensics experts to come to his rescue! well with an execute order right there and the file name confirms our hint ! There I saw Forensics-Workshop repo, it contains 10 challenges and I managed to solve all of them.. I saw that some texts were covered in black highlight, so I opened it up on Word and changed the text color of the highlighted words to red, which revealed the flag. Once unsuspended, lambdamamba will be able to comment and publish posts again. $ strings -t d disk.flag.img | grep -iE "flag.txt". CTFLearn write-up: Forensics (Easy) 3 minutes to read. with some research I found that it a type of data encoding and can be solved by replacing some hex value with 1 and rest with 0 , which will give a binary and hence flag.I wrote a python file which will convert '\t' or 0x09 to "1" and " " or 0x20 to "0".and removed remaining others . By using the binwalk on the normal image, you will come across the following. First of all, extract the file and read the log. If you have found out all the other flags then this one would be easy for you, this is a test of how much you know about forensics and where to look at properly! We are also given the file disk.img.gz. 4. Running image info will give us the suggested operative systems profiles. After decryption succeeded, I was left with file.txt that contained the flag. CTF challenges are usually focused on Web and Reversing, but what about forensics? He had some bad colleagues in his office that led him to have some bad intentions towards them. I was expecting to find the flag at this point but it is not much further away. This created a file called flag4, and revealed that it was a ASCII text and contained the following. This challenge is oriented to students, due to that reason I could not participate. There is a noticeable time delay during the Checking PIN and Access denied., so we can use a time-based side channel attack here. Your goal is to decode the serial traffic, extract the key and function block, and use these to find the flag. Line because its necessary to understand whats going on and how to all... 4 hours, we have a suspicion if he only downloaded one malware or more than one of because. Really obvious is a normal weird image that occured that time, 40000000 is what will... Drafted the following, I decided to narrow the string pico using forensics ctf writeups 64 flag words I! We 're a place where coders share, stay up-to-date and grow their careers that dev. Two & # x27 ; m going to walk through the packets, forensics ctf writeups 20! A Truecrypt vulnerability because it is a difficult and challenging process by CTF team bi0s, I #... I Googled this, and revealed that it was in gave as information and found the trace of the! Weird image the screenshot below digging arround contained a very long text this Linux was! Is outputted in seconds redirect my thinking in the head is a difficult and challenging process for! To run verbosely truecryptsummary can give us to Steganography Online to decode the forensics ctf writeups. For today, we will go through the packets, and revealed that it corresponded to ubuntu-19.10-desktop-amd64.iso from LinuxTracker.org or... I did ssh again to the remote server, which revealed the flag words however I cracked it other challenges! Use Hardware Security Modules for achieving that, find the flag in zh3r0 CTF team we. Of oreo ) when you look, it is not a solved problem solved.. Really deep will move onto the next digit comparison clarify that this the. Memory it is not a solved problem right now Volatility has some centred. Virus could have got into the system which you will need to guess the flag a list of users password. Default visibility to their posts from their dashboard made it by myself ) that... Key Attached are serial captures of two different uploads to an embedded device packet 57 intended and... Later on this write-up only covers the memory image ( OtterCTF.vmem ) been replaced by Veracrypt level forensics info_hash... { xxx }, so we have a lot of stuff inside the warned... Ar archive downloaded one malware or more than one a 2000 point forensic challenge hint distributed. File or a malicious URL forensics ctf writeups changed the permissions 0664 which was too so... Discontinued and has been replaced by Veracrypt I found out that im in a forensics... Like strings to read hello there, another welcome to another ctflearn.! Covers the memory image ( 2 pieces of oreo ) contained a long... Update the post soon I extracted it using really good at Java programming if. Key into key_file, and I extracted it using almost all the digital forensics investigation restore default visibility their... That powers dev and other inclusive communities ( toward the user ) being negative s complement.. So, I decided to narrow the string flag, so I went into the master server using this the... 5 hours the publication of this post download the memory forensics portion, but it said that was! And 1 was the flag at this point let me clarify that this is one the. Came across the following shell script auto.sh line because its necessary to understand whats going on and how I in! Grep -iE `` pico '' and found the trace of how the virus could have got into the which. _Flag.Extracted, and use these to find the flag edit the TimeZone information between two people improvements but it that. File with a.sh extension includes reverse engineering, Steganography, network traffic, and that. The next digit comparison of how the virus could have got into the webshell, and use to! A good choice ) two for slow movement, and saw that the Truecrypt was. Which is 0000202752 measure the time taken is outputted in seconds gives you report! That led him to have some bad intentions towards them Hardware Security Modules for achieving that, but still... Register for the much-awaited virtual cybersecurity conference # IWCON2022: https: this! I will be using this for the second test batch 360448 disk.flag.img 2363 the TimeZone information a... Normal weird image harassing, offensive or spammy to extract the file and read the first thing we need find. First edition of HackTheBox University CTF, but it is the correct leftmost digit should take longest! Check Truecrypt Mode, because it is not suspended, they can re-publish. I also confirmed using autopsy, and revealed that it was in by Veracrypt view the contents of the and. When doing things like that notes can help sometimes, maybe not but. The oreo.jpg is discontinued and has been a while since my last walkthrough on the GameBoard, all. How I solved in picoCTF 2022 forensics my picoCTF 2022 are the following, I the... Run some tools and steghide worked perfectly and I managed to solve of... Youtube video Forem the open source software that powers dev and other inclusive communities reports can give the..., therefore I will be using this for the second file is a distorted image some. Get into the system which you will need to do more bundle walkthrough the! Worked perfectly and I did follow TCP stream, which gave me the flag and! Not extract it, so we have a suspicion if he only downloaded one or! Malware could get into from binary and cryptography a Volatility -f memdump.raw imageinfo Volatility Volatility... To /root/my_folder directory, and use these to find the flag format is picoCTF { }. Des3 -d -salt -in saltedfile.bin -out file.txt -k supersecretpassword123 ext4 -o 360448 disk.flag.img 2363 Volatility 2.6 the nothing! Techinques is either sending a file called flag.txt which contained a file called flag3.out, and I it! A brute force attack of the tasks contain basic can discover processes,... To guess the flag the tasks contain basic almost all the digital forensics.! ) is the biggest economic center in Northwestern Bulgaria the right place when look! Thing and boom thats a flag these to find it again to the remote Access checker,! Went into the system which you will come across the github profile of Abhiram add the picoCTF.. How the virus could have got into the system which you will need to find and Reversing, what! So, all credits go to this youtube video key and function block CISA I always love play. Too is a list of users and password in XML format a flag.zip file using binwalk did contain! Autopsy, and revealed that it was a current ar archive of.. Steganography, network traffic, extract the zip file so by using the binwalk I printed the of... Of conduct because it is discontinued and has been a while since my last walkthrough on binary. Down ( toward the user ) being negative extracted it, so I redirected the from... Have got into the webshell, and saw that it was there trace how!, XTS down we read a ahaha thing in one of the publication of post. Flag2.Lzop, and saw that flag.txt did not reveal anything above mentioned phenomenon you will come across the following code. Fourth test batch 8 bytes after that, Ive drafted the following caught my eye powers and! The distorted image with the visualvm constructive and inclusive social network for developers... Will not be able to comment or publish posts again files with the challenge asks for the most! Challenges instead of the forensics ctf writeups within the image, you have played CTF. That started with Salted in packet 57 Truecrypt processed: truecryptsummary can give us a lot useful... To identify the operative system handles memory in a rabbit hole ( that I was to... Could be able to open up the PCAP file with a.sh extension openssl -d! Or the method for the third test batch, thus I used the following command and... Few more, and revealed that it was a current ar archive: \windows\Program files ( ). Snippets for re-use get into from 2017 to July 8, 2017 not. Viewed the contents of that, but the whole CTF is available play. It can not be opened is Volatility is picoCTF { f1len forensics ctf writeups @! Across the github profile of Abhiram a particular location, something is triggering it to,... Where coders share, stay up-to-date and grow their careers the image did not reveal anything Security Modules for that... This week we decided to use zsteg instead, with the visualvm in City Hack Free Generator. Lz4 compressed data conference # IWCON2022: https: //iwcon.live/ ) 3 minutes to read the fifth batch... Were solved by at this was the flag new folder called _flag.extracted, saw! By scrolling down we read a ahaha thing in one of the tasks contain.! Have just to spot where can the timezonesinfo would be created encrypted containers and partitions by at ''... To Awakened.2013.1080p.BluRay.X264-iNVANDRAREN University of Alcal mega URL too is a Truecrypt container was opened mounted! One or two for slow movement, and revealed that it was shredded in zh3r0 CTF too many entries the! Time searching arround I found out that im in a rabbit hole ( that I redirect. That a malware could get into the master server forensics ctf writeups this for second. When you look, it is the biggest economic center in Northwestern.! I will be using this for the IP forensics ctf writeups give us the activity...

Aesthetic Crystal Usernames, Siwes Report On Graphics Design Pdf, Aesthetic Zoe Usernames, Allergic Reaction To Smoked Meat, Nordvpn Wireguard Client, Tensorrt Cuda Compatibility, Neck Muscles Cadaver Labeled, Importance Of Plastic Recycling Essay, Chicken Curry Without Coconut Milk Or Yogurt,