Questions tagged [decryption]

Process of decoding an encrypted message with an authorized access (knowledge of the protocol, the encryption algorithm and the key).

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1answer
114 views

Recognize a decryption algorithm

I'm trying to reverse a malware that builds its IAT at runtime. Due to my inexperience, I'm having trouble to understand this function that accepts into EAX a dword (maybe some sort of hash) and into ...
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30 views

Decrypting the Config file of a Huawei router “HG630 V2”

followed that post from Wordpress https://hg658c.wordpress.com/2017/12/04/decrypting-configuration-files-from-other-huawei-home-gateway-routers/ Extracted the 4 Hex strings needed. But, looks ...
2
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1answer
29 views

Partially correctly decoded strings from pkware zip with known plaintext

I have a password-protected zip file, where the paths and filenames of each file are encrypted using PKWARE encryption. The password is known and correct, and so is the encryption algorithm. I also ...
3
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1answer
106 views

How does IPA decryption works?

All IPAs being downloaded from AppStore gets encrypted on servers as part of FairPlay DRM. But decryption is accomplished on local device. As far as I know there is some hardware module which contains ...
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1answer
112 views

decrypt config.bin file from Huawei B5328 router i have source files

Hello i need somehelp in decrypting the file config.bin generated by the page backup_setting.html from huawei B5328 router , i have access to all files in the router even the www files hosted on the ...
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115 views

Decrypting Lua Files from game

I'm truing to decrypt LUA scrpits from cocos2dx game (for wiki). Links to files of game: libhellolua.so (cocos2dx external library) example encrypted LUA-scripts (*.abc files) I was reading a ...
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21 views

how can i Encrypt a decrypted zte zxhn h108n V2.5 config file?

i have decrypted the config file using a program i found online ( maybe made by python to exe ) so to decrypt using it you type is command into CMD decode_zte_config.exe config.bin config.bin.xml ...
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68 views

find a video file in memory dump of a process

I have a player that plays encrypted video files and works like this: I open an encrypted video file with it it decrypts the video file and writes it to its memory and plays the file from the memory ...
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1answer
83 views

Determining the hash algorithm used [closed]

I have some test data: Test 1 Text: pass1234 Salt: 33b9d87b83c097ce3ea6e6f84a298f839aafc6d7aa23d909a43ac94bdee35ddf Hash: 61477724c136fb285918114792685a4d Test 2 Text: test1234 Salt: ...
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1answer
72 views

Reverse Engineering Temperatures (RS485 Bus)

I have the following hex byte data. Can someone help me reverse engineer the temperatures calculation? ID || 81 00 8c 00 82 00 aa 00 83 00 04 01 84 00 ff 00 85 00 21 04 The first byte is the id!...
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1answer
146 views

Intercept zip decryption key or files from an application

If an application is reading from a password protected zip file, is there a way to intercept the key being sent to decrypt the zip file. Or, is there a way to dump the files being read themselves?
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48 views

How to guess the key of XOR encryption in java?

I am trying to find the key of XOR encrypted string in java. It is very much probable that the key is eight characters long. I have the encrypted string. I am not able to understand how to go ...
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1answer
103 views

picoCTF be-quick-or-be-dead-1 dcrypt simulation with python

This is be-quick-or-be-dead-1 in picoCTF challenge (Download) in this file we can see decrypt_flag() function, this function return this flag: ./be-quick-or-be-dead-1 Calculating key... Done ...
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0answers
66 views

Sniffing TCP packets using Wireshark

I am trying to reverse engineer a decoder. The decoder contains a web server that makes sending/receiving information through the Internet possible. To do so I need to sniff the packets that the ...
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1answer
295 views

Ghidra pseudocode to Java/C

I have this piece of code generated from Ghidra void __cdecl FUNCTION(uint *key,uint *text) { undefined uVar1; ushort uVar2; uint *puVar3; uint *puVar4; uint *puVar5; int iVar6; uint ...
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1answer
79 views

Difficulty decrypting LCG string

I'm trying to analyze some malware. To get the hang of it I am following the decoding process on this website: Here is a description of the string encoding/decoding process: String encoding ...
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1answer
101 views

Is it possible to recover the key to a decrypted file?

Is it possible to recover the key to a decrypted file if you have the initialization vector and it uses RijndaelManaged? If so how? The file I want to recover the key from is a xml that looks like ...
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1answer
62 views

Can any one de-obfuscator this php code [closed]

my developer has changed all his contact info and i am unable to contact him and i want to move my site to another server but because of this obfuscator code in my php script i am unable to move my ...
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0answers
72 views

Decrypt ibt.sfi linux firmware(Intel Wireless 8265 Linux Bluetooth)

Why I want to decrypt: Intel 8265 Bluetooth is likely a RAMUSB device, which needs system to update firmware. I try to transplant this linux firmware to macOS. Problems I met: The macOS BT firmware ...
3
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1answer
217 views

Reverse engineering file format - ImageLink

I have some technical documentation which is supplied in the form of a generic Windows viewer and a database. The database contains different "books", which are represented by a bunch files: book.bbi ...
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0answers
56 views

1990s non windows software keys [closed]

Hi I am a Service Engineer on some very old ASML stppers that run a system called PAS (Philips automated steppers), these steppers are obsoleted by the manufacturer and no longer supported by anyone. ...
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1answer
149 views

How to identify which iOS kernelcache is installed?

I've an iPhone7 running iOS11.3 (15E216). The ipsw for this build version contains two separate kernelcache files named kernelcache.release.iphone9 and kernelcache.release.iphone10. Neither file is an ...
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2answers
255 views

RSA Decryption? [closed]

I am playing a game in my university where you have different puzzles based on cryptography and now in a puzzle named 'rsa', we have 2 files: 'key', 'secret'. The task for this is to decrypt the ...
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0answers
247 views

Reverse crypto algorythm, based on AES

Hello! I'm working on reversing one library (shared object) written for ARM architecture. It's obfuscated or packed with something pretty strong what makes debugging much harder and almost impossible ...
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0answers
115 views

Reverse engineering key fob checksum

I am trying to reverse engineer the key fob of my Ford Fiesta 2014 but I am stuck at finding the used checksum algorithm. I've successfully demodulates the key fob signal (using on-off keying + ...
3
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0answers
222 views

EEPROM data bytes verification

I'm investigating a tool. I have an section of an eeprom memory dump that this tool uses, shown in the figure below. By my inquiries, the two bytes highlighted in red are based on the bytes ...
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1answer
100 views

how to find private Key and passphrase stored inside a program?

There are some files (drivers) that are encrypted, and these files are working in a program that is installed in my computer. The program using these files needs to decrypt them. I am sure that the ...
3
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1answer
145 views

Help reverse decrypt function (decode -> encode)

I have this java function that decode 8bytes text string(encoded as int[]): public static int[] decode(int[] text, int[] key) { int j = 0x3c; //value 60 in decimal int i = 0x33; //value 51 in ...
3
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0answers
140 views

Guessing checksum 8 bit ASCII algorithm

I am trying to reverse engineer an 8-bit checksum algorithm of a Chinese machine with RS485 communication and ASCII encoding. I tried with all the algorithm I could find, but it seems that data ...
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1answer
346 views

How do i find the decryption key for a encrypted text file [closed]

So context i have a game and a encrypted save file. My thoughts were how to find the decryption key in reverse engineering my game .I watched tuts but i think this topic isnt much detailed so i need ...
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0answers
77 views

File Decryption Problems

over the past year, I provided an English patch to a community of thousands of players of a game I love and which is not available in English (just Chinese and Korean). Sadly, besides me, other ...
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1answer
4k views

How do I decode this JavaScript code? [duplicate]

Each file starts with the same function: (function(_0x128f83, _0x1ae5b9) { var _0x1b5471 = function(_0x339be5) { while (--_0x339be5) { _0x128f83['push'](_0x128f83['shift']()); ...
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1answer
191 views

Reverse Engineering Checksum (RS485 Bus)

I have the following data. Can someone help me reverse engineer the checksum calculation? Data Checksum 01 02 80 05 00 00 00 00 00 7d 8c 01 03 80 05 00 00 00 00 00 ...
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4answers
453 views

Decrypting authorization PHP script

Description I asked for help on freelancing, for the finalization of the project in PHP. All this worked well until I needed to edit the authorization mechanism. Having opened the file, I found that ...
0
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1answer
121 views

Reverse engineering checksum - LG 485 a/c protocol

I'm trying to reverse engineer serial protocol, everything seems straightforward, except checksum byte. Seems to be some easy algorithm - when sum of all bytes is the same, checksum/crc stays the same....
1
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1answer
2k views

Decrypting SQLite Database with key

I have a SQLite database that contains a dictionary (just words and definitions) that can be opened with free but proprietary software. To use with the software, it requires an 'unlock' key, which I ...
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2answers
85 views

How is the IV generated from a timestamp based on this function?

Background: I am currently looking to make some diagnostic software interoperable with other software, but all communication that occurs in this software is encrypted with AES-128-CBC. A sample ...
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4answers
270 views

Decrypting SSL traffic from malware

I am a cybersecurity student. What is the best approach to decrypting traffic from a malware? I am using x32dbg (I'm new to assembly) and have trouble finding the private key. Are there any other ...
1
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1answer
173 views

Reverse engineer CAN-Bus checksum

I am trying to figure out a checksum algorithm. D1 to D6 is data, D7 is a counter obviously and byte 8 must be a CRC, but I didnt have any idea on how to build it. Tried to check if it fits any ...
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1answer
1k views

Need some pointers to decode/decrypt/unobfuscate JSON files (updated with related scripts)

I am very new to this whole business so please bear with me. Goal My goal is to read JSON data from a game. Since I do not know what kind of information will/will not be useful, here are some of ...
2
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2answers
462 views

IDA: call a function with different arguments

I'm reversing some software and found the function which decrypts some stuff: As you can see it has the password parameter for it which gets decrypted in this function. Function disassembly: ...
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1answer
356 views

Unknown game file decompress [closed]

So I got this file with an unknown extension. The file is an event flow code Ok, so I analysed the file (with HxD) and it seems to be compressed in some way because you can read some plain text there....
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0answers
894 views

How to bypass certificate pinning on OS X and Windows [closed]

When reverse engineering a thick application it can be very useful to be able to see the network traffic it generates. Because of this, many applications use HTTPS to communicate with their servers. ...
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0answers
120 views

Reverse engineer checksum in AC Sharp IR packet

i use microcontroller and received ir frame of air conditioner SHARP. This Ir frame have 13 byte data (in decimal number, not hex) like below: 85 90 243 8 131 140 66 0 176 1 32 7 133 85 90 243 8 142 ...
3
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2answers
366 views

how to find the encryption algorithm?

I have an arm complied so file and find the decrypt function which pseudocode generated by IDA Pro is like this: char __cdecl EncodeUtil::getDecryptStr() { int *v0; // r0 int *v1; // r7 ...
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0answers
112 views

Difficulty decrypting nested PKCS #7 / AES router configuration file

I am trying to decrypt a router configuration backup file that appears to be a combination of a 128-byte header, a PKCS #7 encrypted file, and another OpenSSL salted format encrypted file. I think ...
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0answers
341 views

Need Help decrypting .luac files

I have been recently trying to decrypt .luac files inside an encrypted android app. I tried to follow some of the previous threads here but the following frida script didn't give any output. ...
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0answers
328 views

Struggling with an archive file format using “encryption”

I am currently working on a file format used to pack (storage only, no compression) different file types together for transport. There is some sort of very simple "encryption" used and so far I have ...
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1answer
34k views

How to decompile an exe file? [duplicate]

I have been wondering, if every program is based on machine code, can we not decompile a program until it hits machine code and make it up to real programming languages? How to decompile exe files ...
3
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1answer
453 views

Animal Crossing: Pocket Camp .zdat File

Hello I am trying to obtain the music from the new game Animal Crossing: Pocket Camp. The music is contained in files like these: https://download-cdn-ac-pocketcamp.akamaized.net/assets/...