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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2answers
99 views

How can I set up signed downloads?

Scenario I have a web server that authenticates and redirects from HTTP to HTTPS. Clients can then view available "downloads" in their account. I want to be able to sign these download links - as in, ...
9
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1answer
5k views

Where is the salt on the OpenSSL AES encryption?

I'm interested in knowing how and where OpenSSL inserts the generated salt on an AES encrypted data. Why? Im encrypting data in Java classes and need to guarantee that I can use OpenSSL to decrypt ...
4
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1answer
366 views

How can I validate data on RFID chip that has RSA signatures and SHA1 hash values?

I have a RFID chip that has a digital signature using RSA and has data hashed using SHA1. I would like to compare data from the chip and user input in a program but I believe in order to do that I ...
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3answers
238 views

Is a Pattern Lock any more secure then a typical text password? [duplicate]

I've been trying to find a way to secure a webpage that is easy to do (ie gaining access) yet still fairly secure. So, while a 4 char numeric password would be fairly quick to enter, it wouldnt be ...
3
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1answer
183 views

DPAPI equivalent on linux?

I have an app server and a db server. I want to send certain data to the db encrypted, using a DEK (data encryption key). Ideally, this DEK is read protected on the linux file system and encrypted ...
5
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4answers
7k views

How do software keygens work?

I have seen them plenty of times, with many different types of software, but the one thing I have always wondered, is how software keygens know what key to generate. I know the basic principle of it: ...
3
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1answer
800 views

Secure erase iOS devices

All iOS devices from the iPhone 3GS have a hardware encryption chip, right? When you erase an iOS device with the "Erase All Content and Settings" menu item or via Remote Wipe the encryption keys are ...
9
votes
3answers
500 views

Is it possible to prevent a physical attack on full disk encryption?

I've been researching into some methods to ensure that disk encryption keys can't be stolen, and one that I've come across is called TRESOR. With this kernel patch, you can create a partition that is ...
0
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1answer
160 views

How to process or manage Key-Encryption-Key using HSM?

Let's consider two Encryption keys: 1.Data-Encryption-Key(DEK) 2.Key-Encryption-Key(KEK) KEK will be securely stored in HSM, which will be encrypted using master key. Data Encryption Key will be ...
1
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2answers
157 views

What are the security risks associated with storing passwords on the internet?

With products such as LastPass that store encrypted passwords on remote servers, what are the associated risks that aren't applicable to locally stored and encrypted passwords? If something is ...
1
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1answer
492 views

How to Encrypt Credit Card number for storing it in sql server database according to PCI DSS Requirement?

According to PCI-DSS 3.4 Requirement: Render PAN unreadable anywhere it is stored by using the below methods: One-way hash Truncation Index tokens and pads Strong cryptography with associated ...
1
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2answers
133 views

Idea for hiding your mobile phones' location, and still be able to place and receive calls. Any suggestions?

The diagram below is a thought experiment that could provide a certain level of privacy to mobile (smart)phone users, beyond what they currently have. Some of it is purely theoretical, but it should ...
2
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2answers
138 views

Lightweight block ciphers definition

I've read in many papers something that looks an specialisation of the block ciphers calling them with a lightweight tag, but I couldn't found a definition. If I understand correctly, those ...
44
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17answers
3k views

Can we still provide confidentiality when cryptography is outlawed?

In certain jurisdictions, use of cryptography by the private sector is limited: e.g. there are reports that in the UAE and other countries not all of the encryption capabilities of the BlackBerry are ...
1
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2answers
120 views

Nested encryption for multiple users

I've developed a web application (developed in .NET MVC 4) which have multiple users with personal login credentials. The web application holds a lot of content uploaded by the users. My client would ...
1
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3answers
94 views

How to minimise risk to sensitive data in temp files in shared hosting environment before encryption?

openssl_pkcs7_encrypt() requires the data to be encrypted to be read from a file and so unfortunately it requires sensitive data to be written to temporary file before being encrypted. In a shared ...
4
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2answers
142 views

Is authorisation with token secure?

I have a general security question: Let's say there is a client-server application with authorisation by login and password using a secure connection between server and client (https). User can have ...
0
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2answers
133 views

How to know if connection is encrypted

Someone just asked me: How can i know about whether a message or data is encrypted during a transaction on trading website I know most (may be all) online trading sites uses encryption ...
0
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2answers
105 views

Should things that need to be reversed be encrypted?

I was told by a friend earlier that Encrypting something that needs to be reversed is a bad idea as it gives the illusion of security Is this true? The way I see it, it can't really hurt to ...
16
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3answers
2k views

Is it safe to write the salt AND/OR the IV at the beggining of an encrypted file?

I want to encrypt a file with AES in CBC mode (maybe another mode is better for file encryption...I don't know, but suggestions are welcome!). What I usually do is that I first write a few random ...
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1answer
111 views

What is the excellence of RSA vs my algorithm [closed]

I was wondering that what make RSA Asymmetric Cryptography Algorithm special. So I wrote a very simple algorithm that do the same work (Generate Public and Private Key) Now I want to ask you that What ...
0
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1answer
202 views

Which digest algorithm to use with creating a public/private key pair

I'm generating a Public/Private key pair in PHP with the following: <?php $config = array( "digest_alg" => "sha512", "private_key_bits" => 4096, "private_key_type" => ...
1
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1answer
250 views

Why are the first 16 bits of the message digest not encrypted in PGP? [closed]

The first 16 bits of the message digest in a PGP signature are translated in the clear. As we know, sending something in clear text does not sound like a very good idea from a security point of view. ...
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2answers
136 views

Is AES feasible for secure hashing files? [closed]

There was already a similar topic "Why AES is not used for secure hashing, instead of SHA-x?", but it was not about files specifically, and I, personally, am not convinced by the answers in it. "AES ...
4
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3answers
169 views

Android and FIPS

I've recently been tasked with a research project to write a "secure messaging application" using "government approved protocols" (the government being the USA). I'm taking this to mean asymmetric ...
3
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3answers
269 views

What is the most secure way to send emails using PGP?

I am a PGP beginner, having just downloaded GPG for OS X. I created my first pub/sec key for my email address and uploaded it to the public key server. GPG has several features available, namely: 1) ...
0
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1answer
135 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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3answers
864 views

Is “Why Should You Avoid AES In MySQL?” true?

From a 2012 Smashing Magazine article quite a bold statement is made to avoid AES in MySQL itself. Or as they put it "Why Should You Avoid AES In MySQL?". However, if you search for SQL encryption, ...
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3answers
101 views

How to guarantee privacy on files that I store

I want to create an Android app where users from an office (typical use) can upload scanned documents to the app backend service for later use. e.g. A lawyer want to upload a sentence ...
9
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2answers
426 views

Forward secrecy for kids

In the Scouts, it is popular to use secret codes to write messages (which are simple ciphers). I want to introduce Forward secrecy to the kids so they can use it with these ciphers. So, if the ...
2
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1answer
197 views

Does ciphersuite ECDH / ECDHE need hardware acceleration

I have started to read more about ECDH/ECDHE and am wondering if it has the similary issues as RSA - i.e. the processing power required for the decryption of private key is more than of the public ...
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1answer
474 views

Cascading Encryption Algorithm using mcrypt or GnuGP

I'm trying to a cascading cipher encryption algorithm to encrypt a textfile via mcrypt. I'm essentially trying to emulate the behavior of TrueCrypt, where it can cascade two or three different cipher ...
2
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1answer
249 views

AES in CTR mode with same random IV to create same ciphertext

I am currently working on a little project. I am trying to generate an AES key with that I would like to encrypt a private RSA key. I have to do it this way. However, I do not want to save the AES ...
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2answers
4k views

Decrypt cipher texts encypted with the same one time pad key

I have two pieces of ciphertext encrypted with a stream cipher using the same key. How do I recover the plaintext of both ciphertext messages without knowing the key used?
3
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4answers
439 views

What are the features of Dual EC DRBG that are lost when using a different cipher?

Due to a potential NSA backdoor, the NIST is now recommending that implementor no longer use ECC-based PRNG Dual EC DRBG. (As described in Wired.com) this PRNG has certain features such as: ...
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1answer
87 views

Permutation in Block Ciphers

I was reading some e-books to understand the basics of block ciphers and how it works in AES. As i understood, Permutation plays a big part in AES and Block Ciphers, Here is what i understood by ...
1
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0answers
119 views

Tools to perform benchmark of block/stream ciphers on Linux? [closed]

I would like to perform some benchmarking of different block and stream ciphers for general data (lossless and lossy data) encryption and decryption (with focus on power consumption). To get general ...
0
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1answer
78 views

What is the weakness of OFB in 8bit mode?

I'm currently trying to understand the difference between "regular" OFB with full-block feedback and OFB with 8-bit feedback and, in this context, the difference between this two modes regarding ...
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2answers
81 views

Executing PHP WeService script by clicking a link within an e-mail

I'm receiving e-mail from my PHP/MySQL application with certain links. I was thinking on including an UUID as part of the link, which would point to a Web Service that ONLY reads those UUIDs. Those ...
25
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8answers
2k views

Share certain information only after death

After your death, you want to make sure that a special someone gets a vital piece of information (like the password to your bank account), but: You don't want anyone else to be able to get that ...
3
votes
1answer
84 views

Can we build a key exchange protocol without certificates?

Assume that the server and the client both has some secret key K. Is it possible to have a key exchange protocol with authentication between them such that MITM attack cannot hold and if the key is ...
1
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1answer
76 views

What is the strength of the key derivation function on Android device encryption?

What is is strength of the key derivation? Specifically, how many milliseconds or microseconds would it take a desktop computer to check a guessed password to see if it is a match? I am aware this ...
0
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1answer
51 views

SAML2 encryption

I am new to SAML2 and have a question. We have a customer that is saying that they want to encrypt the user data they are sending to us. Here is an overview of how I have this implemented today: User ...
2
votes
3answers
96 views

Limit attempt of user login against PBKDF2

I have been tasked been tasked by my boss to change the encryption system of our web application from MD5 to PBKDF2 as MD5/SHA1 has been shown to be breakable in recent years . I argued against it ...
0
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1answer
29 views

Is embedding the EAX nonce inside the Associated Data considered safe?

As the nonce bits would be used twice in that case, does that break EAX security? The examples I've seen using EAX have separated the nonce from the Associated Data, but to me it makes more sense to ...
0
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1answer
107 views

Protecting user data via encryption

I am working on a fitness app, and it is going to have the following user data: email, first name, last name, birth date, height, weight over time, Body Mass Index over time and heart rate over time. ...
0
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4answers
101 views

How does an encryption key work? [closed]

I'm having trouble understanding how an encryption key works. for example: if the word was 'hello' its encrypted value could be 'GHSSDgsd2', what would happen to the encrypted value if the key was ...
3
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8answers
2k views

Secure alternative to e-mail

After the announce that NSA conducts extensive metadata and traffic search on e-mail, it is clear that people looking for privacy and security would better abandon the system completely, since, by ...
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0answers
29 views

How does an encryption key work? [duplicate]

I'm having trouble understanding how an encryption key works. for example: if the word was 'hello' its encrypted value could be 'GHSSDgsd2', what would happen to the encrypted value if the key was ...
3
votes
1answer
264 views

How do I verify exactly which cipher suite is in use for this Remote Desktop session?

You can configure Windows to use only certain cipher suites during things like Remote Desktop sessions. Cipher suites such as RC4 56 bit, RC4 128 bit, Triple DES 168 bit, etc. SSL/TLS is not in play ...