In cryptography, encryption is the process of encoding information. This process converts the original representation of the information, known as plaintext, into an alternative form known as ciphertext. Only authorized parties can decipher a ciphertext back to plaintext and access the original information.
Questions tagged [decryption]
262 questions
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How can I force slow decryption in the browser?
I have a string that I will encrypt on the server. I then want to send the encrypted string along with a decryption method for it to be decrypted in the browser.
I want the decryption to take some time for the end user. Let's say ~10 minutes.
Let me…
Sprout Coder
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How to decode "SELF-SHIFT" cipher?
I try to use the function
$$C_i=E(M_{2i}, M_{2i+1}) = (M_{2i} + M_{2i+1})\bmod 26.$$
to encode English text.
For example,
Plaintext: The quick brown fox jumps over the lazy dog.
Regrouped Text: TH EQ UI CK BR OW NF OX JU MP SO VE RT HE LA ZY DO…
Alex-Github-Programmer
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Decrypt a ciphertext knowing of a pattern of key repetition
I have two ciphertexts (I do not know which encryption algorithm was used to create them) which both starts with the same 3-characters long word.
This led me to believe that the same key was used for both of them and that I could exploit that to…
Rich
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Vigenère cipher SECRET
Decrypt “jjjj aaa cccc ddddd” using Vigenère cipher with the key “CONVO”. I used 2 different generator and online calculator and i am getting 2 different results
Secret Admirer
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Decrypting a polyalphabetic cipher
I'm currently trying to crack a ciphertext with three rotating substitution ciphers. I've tried dividing the cipher up into three parts and do text frequency analysis since I know the language but no luck when trying to peace together the parts. It…
user99620
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My fernet key "expired" what now?
6 months ago i created a bot that basically stored every users data in json format in different text files and i had a fernet key. I basically didn't touched it for like 2 months now, because it's a bot for students. So here is the thing, school…
Moldender
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Need to identify cryptographic algorithm
I have a binary code which decrypts some 64-byte data chunks.
There is a decryption key which is always static, and there is a code which does actual decryption.
What I need is to find out which algorihtm does it use (probably it is something common…
MarSoft
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What's a relatively fast way of checking if a string is decrypted English?
I asked this on Stack Overflow but I was told to ask here.
I'm writing a program that decrypts text encrypted using a Vigenere cipher. It's been working very well so far, but my current issue is that I need an effective way of checking if a string…
paper man
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I know my passphrase. I don't remember specifically how I entered it
First if this is the wrong place to post this please forgive me.
I know my passphrase. I don't remember specifically how I entered it. ex. If the phrase is "The house at the end is blue and white. I like it." I would have used the first letters of…
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Black box solver
I want to know if there is any mathematical or brute force approach to decipher simple black box
A: Is only one digit (0...9)
B: Is 2 digits (00..99)
C: Is a result of a linear function between A & B, for example it could be C=A2+8-10B or C=A*A-B…
Jackal
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