Encryption is the process of transforming plaintext using a cipher to make it unreadable to anyone except those possessing the key.

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Is asymmetric encryption vulnerable to man-in-the-middle attacks?

I'm looking for ways to send private messages over a public channel, and in doing this I stumbled in asymmetric encryption, which is just perfect for what I was looking for at first - A and B ...
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1answer
269 views

How can brute force scripts tell once they're found the correct key?

If you have a random block of data and you encrypt it with a key, how can a brute force script tell when it has found the correct key? Is it possible without some sort of reference to the original ...
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2answers
864 views

Is SSH secure and what are the recommended modes of operation?

Given the recent confirmation of weakened and broken encryption schemes and implementations, how does the community feel about the security of SSH? It seems there has been very little discussion ...
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1answer
196 views

Any issues with this security design for cloud storage? Server doesn't even need to know password to log someone in

I've created an algorithm I think I'm going to use for a cloud storage service I'm developing- if there are no issues or vulnerabilities with it. It's this along with TLS and forward secrecy ...
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1answer
95 views

How to change TEA round count? [closed]

I cribbed the public domain TEA source from wikipedia ( http://en.wikipedia.org/wiki/Tiny_Encryption_Algorithm ), looks like this - uint32_t v0=v[0], v1=v[1], sum=0, i; /* set up */ ...
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3answers
144 views

Best way to store passwords for a LAN tool?

I am making an app in Python for linux as a front end to the router (to automate some tasks). But I need to log in to the router before I can do any operations on it and since it uses a http-auth I ...
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2answers
4k views

Risks of client-side encryption using Stanford Crypto Library

I'm building a simple web application for encrypted chat. Each message will undergo 256-bit AES encryption on the client side, using the Stanford Javascript Crypto Library. No unencrypted data or ...
0
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4answers
238 views

Is knowing 'a' encrypted with 'b' and 'b' encrypted with 'a' a possible threat?

Excuse me for question name, but I couldn't find any other suitable title. I want to validate client connecting to the server. My algorithm looks like that: Clients sends his login - plaintext ...
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2answers
3k views

What are the vulnerabilities of using a 256 bit encrypted PDF file over email?

I often send confidential documents to others using encrypted PDF files (i.e. files with a user password, and typically with an owner password as well) to prevent both accidental forwards and ...
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2answers
2k views

Look over my Web API Authentication Scheme

I want some advice on my Authorization/Authentication scheme that I will be using for my Web API that I am writing. Firstly the Authentication : 1) When a user first logs in and they are authorized, ...
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2answers
1k views

Does the haystack theory work

The haystack theory is the recommendation to put repeated characters in your password in order to make it harder for brute force to reveal. Does this have any mathematical basis? Or is it snake oil?
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3answers
148 views

Basic simple encryption with already installed tools

If you are exchanged email messages with people using Linux, Windows and some odd Mac and want to implement some really basic security, encrypting all messages, just trying to avoid some ...
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1answer
5k views

4096 Bit RSA Encryption Cracked [duplicate]

I'm new to encryption and still learning about it; I overheard someone this weekend mentioning that 4096 bit encryption was "cracked" by listening to the CPU and searched for this to confirm it ...
4
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1answer
307 views

Securing wifi with encryption

So I have been hearing that using WPS Pin is not secure at all and that there are available downloads that can brute force attack the pin until it uncovers it depending on what encryption you use. I ...
0
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1answer
897 views

How secure is a partial 64bit hash of a SHA1 160bit hash?

So http://en.wikipedia.org/wiki/SHA-1 SHA-1 produces a 160-bit (20-byte) hash value and As of 2012, the most efficient attack against SHA-1 is considered to be the one by Marc Stevens with ...
2
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2answers
658 views

Consider a “zero-knowledge” file host such as mega.co.nz. How can one prevent users to upload unencrypted content?

I am wondering how could a zero-knowledge host such as mega.co.nz prevent users to just upload files in clear, and, for example, to discredit the site by uploading a large quantity of illegal material ...
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1answer
131 views

What is this encrypted with or where can I find examples of encryptions to compare it with? [closed]

I have a hash thingy I am trying to decode and I have done relatively little with encryption, though I would like to try to learn some more. The hash is: 1YMTpavsFq7ykllC3CCsg3e1li31re1nROxuW1wqIqpk ...
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4answers
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For someone who has a key and ciphertext, is it possible to find out what encryption algorithm was used?

For someone who has a key and ciphertext, is it possible to find out what encryption algorithm was used?
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1answer
3k views

Token authentication and storage / websocket issues

My application is running an API authentication that uses tokens rather than cookies. This leads me to ask a few questions : What is the most secure way to store the token ? By using random ...
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2answers
65 views

Challenges in authentications

I have a case where I have a set of low compute capable processors connected to a gateway processor. I need a way of authenticating these processors to gateway processor. The main things are: I need ...
2
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3answers
586 views

Does HTTPS encryption work when there is invalid or there is no certificate?

When I have a website run on https and there is no certificate, there is wrong certificate or out of date like here does encryption still work or not?
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2answers
337 views

Is there man in middle attack when using mobile phone calls?

My question is about the encryption between me and my mobile operator. My mobile operator uses A5/1. I use Samsung. Sometimes I see the symbol G on my phone which means GPRS. I don't know whether it ...
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2answers
265 views

Securely passing critical data to other domain

My company owns a domain A.com , and subsdiary is on B.com B.com redirects their users to A.com for accounts registrations. Post successfull registration , A.com logins that user ( User doesnt get to ...
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1answer
74 views

using asymmetric encryption to encrypt private key [duplicate]

Just a small question: I know it is common for one to use asymmetric encryption in order to encrypt his private key, when using symmetric encryption. Is there a name for this process/method of ...
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1answer
438 views

Encrypting content using same secret key as hash?

OK - I'm trying to design a system that can provide personalised/differentiated content at minimal expense to the server. One of the designs I'm currently exploring is where the request is somehow ...
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3answers
4k views

How To Recover EFS Cert From Backup?

I made a backup of the old Win 7 Pro then did a clean install. But I forgot to export my EFS encryption certificate, so when after I restored the encrypted files from backup I could no longer access ...
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1answer
258 views

Password algorithm to be integrated on a website

I have recently started a project to code a secure password protection algorithm to be used on both computers and mobile devices. As I have never done anything like it before, I am a bit unsure of ...
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2answers
772 views

TPM- Symmetric key storage

I understand that the TPM can be used to store an unlimited number of keys. However I am left with a few questions: Presuming the TPM is connected on the LPC what protects the data travelling across ...
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1answer
4k views

What does chacha20-poly1305@openssh.com mean for me?

OpenSSH just introduced a new protocol, chacha20-poly1305@openssh.com, which combines the two algorithms from DJB: ChaCha20 and Poly1305-AES. It was inspired by a similar proposal for TLS, which ...
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2answers
588 views

Metadata-free Email: How can SENDER directly, anonymously, and securely ask RECIPIENT’s mail provider to deliver a metadata-free email?

If I want to send emails to friends who use Google, Yahoo, AOL, etc., how can I currently use my local email client to send a metadata-free* email to them? E.g., is it possible to bypass my own mail ...
3
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2answers
230 views

Using public key infrastructure or hashing for personal identification privacy?

I've been reading about identity theft recently, and I'm wondering about some possible solutions using the techniques of asymmetric/symmetric/hashing in encryption. My idea is going to cross those 3 ...
4
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3answers
799 views

Can a zero knowledge proof of voting be made using a trusted auth server (without client side crypto)?

Questions: Can one implement a secure voting system having all the features described below? e.g. without disclosing any individual's vote to the government server (or the third party), preserving ...
3
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3answers
661 views

Is there an attack that can modify ciphertext while still allowing it to be decrypted?

Is there any way an encrypted file using AES-256 could be modified without alerting the file owner, ie., so it can still be decrypted with the same key? I know that without an initialization vector ...
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0answers
157 views

Putty Event Log

Can anyone explain me the Step by step process of Key Exchange that takes place while accessing Linux machine using Putty ? I found the Event Log of Putty but the Various Key Exchange didn't make very ...
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0answers
142 views

How do time-limited keys work for e.g. DCP files?

According to http://en.wikipedia.org/wiki/Digital_cinema under How Digital Cinema Works it states that the decryption keys are time-limited and expire after the end of the booked time. From a high ...
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3answers
663 views

Is applying AES multiple times safer?

The KeePass security help page talks about preventing dictionary attacks To generate the final 256-bit key that is used for the block cipher, KeePass first hashes the user's password using ...
3
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2answers
279 views

How are WPA Keys stored on a router?

Should the router only store a hash of my encryption key or is it stored as plaintext? I believe (but not certain) that the WPA key is itself an encryption key, buy shouldn't that be encrypted like ...
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5answers
899 views

Authenticate user without knowing their password

I'm working on a project where each each user will have a public/private RSA key-pair. Users will be able to send encrypted messages to each other using the each target user's public key so that only ...
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1answer
150 views

Advice on using encryption for self training app

I am self training on using encryption. I am a php developer and in my spare time I am building an online app that provides basic cms features to help me understand encryption design more. I am using ...
3
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3answers
517 views

Backup personal email on VPS - privacy, security and trust risks

FastMail.fm hosts my personal email account. Now they claim to have reliable backup services, but I'd like to have my own copy of my email archives. What I'd like to do is back up to my VPS, which ...
0
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1answer
53 views

PPTP and Split Routing

If I uncheck the "use default gateway on remote network" to be able to browse local shares and the internet at the same time, does that void encryption?
0
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1answer
367 views

MD5 Algorithms in web development

I am storing the passwords of my college website in our own server. I am storing the passwords using the MD5 encryptor. But the doubt I got is since the decrypter is there I can also decrypt the ...
0
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2answers
567 views

Difference between free ssl and non-free ssl? [duplicate]

I am making a choice between StartSSL and positiveSSL($4.99/yr). I want to know the difference between them. As I know, SSL is used to encrypted the connection between client and server so that data ...
2
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1answer
117 views

Layered email encryption with multiple private keys on separate media

I'd like to encrypt e-mail messages so that multiple physically separated keys are needed to decrypt them. For example, I'd like to have three private keys stored on different media, as in: key A ...
0
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3answers
332 views

How to store user credentials like Mint.com [duplicate]

If you have a website that need to store user's credentials for other sites, how do you store those credentials securely? An example is Mint.com where you give them your username/password for your ...
1
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2answers
279 views

Two-factor port-knocking via SMS (TXT)

It seems to me that a useful alternative or supplement to traditional port-knocking, fwknop, etc, for a system requiring only occasional access, would be to: Set up a one-time pad of keys, and a ...
1
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1answer
431 views

How does the MITM (Man in the middle) attack happen with respect to SQRL

I recently looked into SQRL and was intrigued by its simplicity. At first glance it seemed reliable and its author claimed it was inherently fail-proof against phishing and MITM attacks. But upon ...
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2answers
390 views

Encryption method and other security concerns for a simple password manager [closed]

I thought I would learn a little bit of cryptography programming by making myself a simple password manager program that I can potentially even use to keep track of my passwords. The idea is that my ...
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1answer
402 views

What are the risks if a weak ciphers are accepted by a technology that uses SSL

The TLSSLed tool found that the host that I use has SSL connection that accepts 8 different TLSv1 and SSLv3 ciphers that are weak by their length (40 bits). How can an attacker exploit this fact?
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0answers
92 views

Does the ordering of encryption and hashing matter? [duplicate]

I am now learning keyed hash function, where A and B share a secret key k. I want to know if the ordering of encryption E and hashing H matters? i.e. Is there any difference between H ◦ Ek (m) and Ek ...