Questions tagged [hash-functions]
An surjective function that maps a set of keys to a smaller data sets of a fixed length. Cryptographic hash-function are supposed to be practically impossible to reverse except by brute-force.
21 questions with no upvoted or accepted answers
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Reverse Engineering a 8 bit CRC checksum
I am trying to create a communication interface using C Language to an Air conditioning system, after analyzing the data packets I have identified that the data packet is consist of an 8 bit CRC (I am ...
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How to decrypt query string of an url
I need to decrypt the encoded part of query string i.e. Q7eM0euncHNyrhJPjN06lw== and sWmYdMUi01BJplzumEaxTw== from the following urls?
https://XXXX/deed-check/view-deed-summary?encApplicationId=...
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Identifying a hash function knowing both input and output
I am creating a custom client for an old game. Now I got stuck on login to the server. I made several experiments with wireshark but it doesn't seem to be any common hashes.
From my limited ...
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How to find how a hash in generated in an iOS app
I'm currently working on an iOS app to replicate a signature which looks to be generated with a MD5 hash. I'm currently using Frida, but haven't had any luck replicating it. I've used the script to ...
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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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What checksum is Super Smash Bros. Wii U using?
When you save a screenshot in Super Smash Bros. for Wii U on the SD card it writes to, it makes two files: a .JPG and a .BIN file. Both these files are in the format of HNI_XXXX.EXTENTION, where XXXX ...
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can sha1 hash of file converted to sha2 hash?
I have a phone database /data/user/0/com.miui.gallery/databases/gallery.db containing information such as exif data and file name. there is a column sha1 containing value
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Where can I find the hashing algorithm in source code?
When I submit login credentials in an Android Application it POSTs an encrypted string to an API endpoint.
For example, if I enter the following email & pass :
"[email protected]:abc"
it ...
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Techniques for reversing (basic) hash function
Hi I'm relatively new to RE, and I'm using GDB and Radare2. As part of a crackme I'm trying to reverse a weak hash function that's a little too complicated for me to undo by hand. I've been trying to ...
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Reverse engineering a hash generated from IP and unixtime - How to approach?
There is a website that gives you a token and the unixtime to access a resource on another domain.
I can use those 2 values to access it like that:
Example: example.com/test.txt?st=[HASH]&e=[...
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Reverse engineering Nextbike API and random 16 character pre-shared key
I am trying to get to know how Nextbike's API works. It's not a public API but capturing the outgoing traffic with my phone I can see all the traffic and endpoints that are being contacted.
I've ...
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can we decrypt a hash function of SHA256
if i have a hash SHA-256 , i want to decrypt it i know that result is in the format of string of length 40 which contains both small and large alphabet and 0-9 number (randomly)
which method i have ...
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Restoring hashed filenames from Juiced (2005) DATs
Where is the memory address for the hash function from Juiced PC executable to restore hashed filenames?
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Figure out iButton hash of known stored value in 6 bytes
I have an old iButton which stores a floating number on 6 bytes, presumably using a checksum, for which I can't figure out the algorithm.
Here are samples I have:
value X1 X2 X3 X4 X5 X6 V1 V2 ...
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Unknown file analysis
I have a file, which supposedly contains an output of CRC32 hash. Problem is, file has no extension, type file (cat analogue) returns mangled gibberish, i.e. ёя╫жW▲{═Sb╨y¶|ИМ▐ВQ╙l9k╖▀у║?╩↓b☼┐R.
TrID ...
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Determining a password-hashing function knowing plaintext + output
I have a password that has been stored and I'd like to figure out how it's been 'transformed' to be stored in my database.
The plaintext password is:
k4oK203$
And the password as it is stored 'crypted'...
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Hashing algorithm of length 50
I have been trying to reverse-engineer an Android application using Jadx for static analysis and Frida for dynamic analysis. The end goal is to be able to re-create the request signature, sent as a "x-...
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cracking SHA256 if you think you know its original value but don't know which is it
I have a hash and what I think is its original value
DRMSoftwareRadio-MERLIN-00000218
20030130
Frank Garnier
[email protected]
Witte Kruislaan 55
Hilversum
1217AM
Netherlands
...
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Reverse Engineering a Vehicle Identification Number (VIN) encoding
Not sure if this is the right place so please point me to the right place if needed.
I have an input of a VIN (Vehicle Identification Number) number with 17 characters, each character is either an ...
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Does anyone recognise following (USB,HID?) encoding method?
Im reverse engineering a Keyborard RGB LED Control Software and there is a Library called "HidServ.dll" that seems to be the interface between the Keyboard and the Software. Every Function of that ...
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Reversing sha1 hash with 2 captured hashes
As an exercise we need to reverse a SHA-1 to get the 'original' message.
All we know is that the lowercase SHA-1 of the code gives:
B39ECFBC2C64ADBB7C7A9292EEE31794D28FE224
And, the SHA-1 of the ...
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