Questions tagged [decryption]
The process of decoding data that has been encrypted into a secret format.
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Is there such a thing as a "Black Box" that decrypts Internet traffic?
I have been reading about the Snoopers charter bill that was passed in the UK this week.
It mentions a "Black Box" which is cited here: ‘Black boxes’ to monitor all internet and phone data.
It ...
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Is there any hope of getting my pictures back after an iPhone factory reset some day in the future?
Four months ago I lost all my data after an iTunes update automatically restored my phone to factory defaults. I lost all the pictures of my newborn.
I understand that when you do a factory reset the ...
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Why haven't (most of) the Zodiac Killer's letters been decrypted? [closed]
The Zodiac Killer was a serial killer in the late 60's and early 70's. The twist is, he would frequently taunt the local press with cryptic letters. Four of these letters were actually encoded, but ...
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How to decrypt .lock files from ransomeware on Windows [closed]
I am helping a friend which is an accountant and got all of her books locked due to this. Here are some details:
BTC address of the attacker:
1MBwkTssJkqRvXmAFcSEZ3xTD39A9rkyYA
Email:
helptoyou1@...
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3
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Why does an encrypted message sometimes end in "=="
As a programming exercise I need to decrypt a message. The only clues that I have is that it seems are:
The encoded message contains only Base64 Characters
a n letter sequence (n in 1,4,7,10) times ...
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6
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Is it possible to recover a lost passphrase for a private key file?
We have a set of public and private keys and certificates on the server. The problem is that while public encryption works fine, the passphrase for the .key file got lost.
So, when trying to execute ...
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7
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Encrypting text file with AES 256 instead of password manager
I'm starting to have a big list of passwords I need safely stored. I was looking at password managers like LastPass, but these always seem to be targetted by hackers and have been compromised before.
...
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4
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CryptoWall 3 - how to prevent and how to decrypt?
My father's computer is now infected with CryptoWall 3, according to the link below.
http://www.bleepingcomputer.com/virus-removal/cryptowall-ransomware-information#CryptoWall
Is there a way to ...
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4
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Has anybody successfully decrypted their files after paying the WannaCrypt ransom?
WannaCrypt is a shot heard 'round the world, for sure.
I have seen news articles saying that people have paid more than $20,000 in ransoms. Here's one from Krebs: Global ‘Wana’ Ransomware Outbreak ...
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4
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How To Recover End-To-End Encrypted Data After Losing Private Key?
I'm creating a mobile app which has chat feature in it. Since I wanted to make it secure, I'll do some encryption to messages and the data. I'm thinking of using End-To-End encryption for it but I've ...
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Are these claims about modern CPUs and AES decryption true?
Because of the format this question is in, it was a toss up between posting it to this site or Skeptics, but I went for here in the end because I'm probably more likely to get a definitive answer.
...
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How trustable are third party root certificates?
I recently tried to use Fiddler2 from a third-party vendor Telerik. While decrypting the HTTPS traffic of my network, it asked me to install its own root certificate in my Windows operating system:
...
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1
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Extracting openssl pre-master secret from apache2
I would like to be able to decrypt my server's https traffic for debugging and analysis. My server is a debian 9 Apache2 server running mod_wsgi and django.
I have seen this post:
Extract pre-master ...
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5
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What will I get if I "decrypt" a plaintext?
If an encrypted text is decrypted with its corresponding key, we would get the plaintext. However, what if I were to decrypt plain text? What would result? An error or some nonsensical number?
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If a WAF is compromised, can the adversary view all the traffic in clear text provided WAF uses SSL cert to decrypt it?
I understand Web Application Layer Firewall (WAF) uses an SSL cert to decrypt and inspect the traffic before passing to the backend server. If an attacker could gain admin access to both the WAF ...
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Is it possible to decrypt half of a TrueCrypt file container if the other half of the data is missing?
Let's say we have half of a TrueCrypt file container (e.g. download was interrupted). If we know the password, is it possible to open it and get half of the data? The original container has 10 files, ...
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1
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Can I decrypt my SD card with another phone?
I found this answer in an old 2016 post, and I have the same problem.
I encrypted my SD card and when I unencrypted my phone, I didn't realize I needed to unencrypt the SD card first. To be honest, I ...
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2
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Private key to PEM
I'm new to security and I'm trying to decode some SSL encrypted communication between my machine and server. I managed to obtain private and public keys
as far as I understand private key is this one:...
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How to read password from Windows credentials?
What is the cipher used by windows Credential Manager to generate credentials backup files (*.crd)?
With a backup file from Credential Manager and the password used to created that backup file is it ...
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3
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What makes a symmetric encryption algorithm cryptographically secure?
I'm trying to learn a bit more about symmetric encryption and found out that basically every symmetric encryption and decryption is (somehow) in the end based on a simple XOR-Byte-Toggle with using a ...
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How are Tor packets decrypted on the client?
I am a bit confused about packet decryption of Tor on the client.
I understand that if a client sends a request to a web server by using Tor, the request will be encrypted a couple of times, and ...
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Intentionally slow decryption
We need to store the user ID of authors of messages in a database.
It should be possible to find an author of a problematic message i.e. on police request in minutes, but it should be very hard to ...
7
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3
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How to deliver an encrypted message to multiple recipients without revealing keys
Let's say I have generated a private and a public key. I create a message and encrypt it with the public key. I deliver this encrypted message and a private key to multiple recipients.
Why would I do ...
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3
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Why can't the FBI copy the contents of an iPhone they are trying to crack?
Making the news rounds now is a story about the courts ordering Apple to disable the automatic deletion of data after 10 failed password guesses.
What I don't understand is, why doesn't the FBI just ...
7
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4
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How can I decrypt a Word document that I know the password to without opening it in a word processor?
I got a question that I thought would be simple but it is proving to be more difficult that I thought it would be.
I got a malicious password protected Word document that I want to analyze for IoCs. ...
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7
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1
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Log all crypto keys used for outgoing SSL / TLS connections on Linux server
Is there some environment variable that works how SSLKEYLOGFILE works for NSS-reliant programs but which would apply to all outgoing TLS / SSL connections on a Linux server and not just ones that use ...
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1
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In PSK TLS, how is the key used for encryption derived?
I'm trying to decrypt a message sent over a secure communication channel using TLS_PSK_WITH_3DES_EDE_CBC_SHA. I now have the client random number, server random number, PSK identity and PSK value. My ...
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Decrypting SSL using Wireshark on Linux vs Windows
I'm working on decrypting my own traffic that gets sent through Wireshark and I've been following this guide for reference. I have been using the SSLKEYLOGFILE environment variable and I can get the ...
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6
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Managing the public keys and certifications of S/MIME protocol
I don’t have any experience in the security field, and I want your help. I want to ensure if the following suggestion is applicable and secure, if it’s not, please give me your suggestion to solve the ...
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Decrypt chunks of pgp encrypted
Suppose I have a very large encrypted .csv file (too large to fit in memory). Is there a way to decrypt N bytes of the cyphertext? My goal is to process each row of the .csv in memory without ever ...
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5
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3
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Decrypt TLS 1.2 traffic between .NET Windows applications
I have attempted to decrypt traffic between two .NET applications (both on Windows platforms) using Wireshark but due to the Diffie Hellman with perfect forward secrecy, I cannot use my private key ...
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Unable to obtain TCP/HTTP traffic from WPA2 packets even with full handshake and decryption
The Problem
On my WPA2 network, I have been successfully able to get intercept a full four-message EAPOL handshake from a particular computer on my network. It is my understanding that with this ...
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JSON data decryption
Context
I am trying to learn more about web security through looking into how various iOS native apps work under the hood. I have been using Burp Suite as the MITM tool to sniff out the network ...
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Decrypting .P7M File with Key (.pem) using OpenSSL
My knownledge about security is limited so I need some help here.
The Question
I want to Decrypt a .P7M file using its private key (.pem). I would prefer to use OpenSSL for this.
Tried so far
...
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gpg does not require passphrase to decrypt
Suddenly the behaviour of gpg has changed and my world crumbles.
I have several keys, all but one for testing purposes. The one is my personal key. Up to now I have been able to encrypt with this ...
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5
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1
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Which file encryption algorithm is used by Synology's Cloud Sync feature? [closed]
I'm trying to find out which encryption method is used by a piece of software I use, viz. the 'Cloud Sync' feature of Synology's DSM 6.0 running on a Synology NAS.
(Background. This Cloud Sync ...
5
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1
answer
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How to decrypt Diffie-Hellman encryption in WebRTC?
I have installed a WebRTC server application, which is designed for Contact Center solutions: communicates with internal PCs in pure RTP (agents), and with external PCs (customers) using encrypted ...
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How do I know which padding was used in a cipher suite?
I am trying to write a java program that decrypts tls packets. I want to use the Cipher class. From the Handshake I know that e.g. my CipherSuite is 0x00 0x2f which is TLS_RSA_WITH_AES_128_CBC_SHA. So ...
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2
answers
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Web-based secret manager using CryptoJS
I'm building an application, part of which will allow businesses to store secrets.
I'm looking at using CryptoJS (https://www.npmjs.com/package/crypto-js). This would encrypt everything on the client ...
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How to decrypt a message using only session key?
I can view a session key to the encrypted data using option gpg --show-session-key <file>.
Knowing the session key, how can i decrypt the data without using my private key?
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What happens to PKI once quantum computers can break encryption?
They say that public key infrastructure or PKI uses very complex encryption. What if that encryption breaks one day when quantum computers complete? What if they decrypt all private messages and data? ...
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Company decrypting SSL, is it common?
We've just implemented a proxy that decrypts all SSL traffic in order to classify and scan it. Naturally a lot of our users feel concerned. We're a small company (100 users) owned by a big company (...
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How long does RSA encryption/decryption generally take?
I am going to encrypt and decrypt a base64 that's an image. Now it needs to be fast. How fast does it take to encrypt and decrypt a file with RSA-OAEP for example?
And if it is too slow what is a ...
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Is decryption of past conversations a legitimate concern?
Suppose sensitive information is sent over an insecure channel, but it is encrypted with a cipher such as AES. As of this writing AES is not broken and brute-forcing it would take more than millions ...
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What would be a simple example of an asymmetric encryption function (asymmetric function)?
I am trying to understand RSA encryption but the algorithm seems quite complex.
I know that with asymmetric encryption you use a key and a function to encrypt data and a different function to decrypt ...
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Can you ever get partially decrypted data from a decryption algorithm?
I'm decrypting some data using Java and Apache's most recent WSS4J library with 128-bit AES decryption.
I setup the the cipher which appears to be correct with the right padding, decryption algorithm,...
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1
answer
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Where are the symmetric keys stored when using ssh?
The use case is this: Imagine you have two systems, A and B. If system A ssh's into system B and begins transferring over files back to A, I want to be able to decrypt the content of the message being ...
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How can I decrypt a file with gpg to screen and not write to disk?
I currently use a script to decrypt a file, but it writes it to disk. I then use wipe to clear it. Is there a way to write it to screen so it never writes it to disk?
I use the command $ echo ...
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2
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Is it safe to encrypt my password with the password itself?
I'm using a password to encrypt some data. However, upon decrypting, I want to check if the entered password is correct. In order to do so I encrypt the password itself. Then upon decrypting, I check ...
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3
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How do you find SSL Keys on Android (to decrypt SSL on WireShark)?
I'm using an Android Emulator on my PC, then logging into some apps (while running WireShark), and now I'm trying to figure out how to decrypt the SSL traffic.
I understand that I need to find some ...
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