Cryptography is the practice and study of logical means used to achieve information confidentiality, integrity and authenticity. It covers, among other things, encryption (making some data unreadable except for those who know a given secret element, called a key), data hashing (in particular for ...

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How can i store encryption key into Microsoft provided Key container?

I'm working on an application in which user will enter encryption key via GUI and my app will fetch that encryption key. Now i need to store that received key into Microsoft key container. I got this ...
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1answer
53 views

Which stream ciphers are supported in am335x cryptographic accelerator?

I want to use cryptographic accelerator in aes cfb mode [or any other stream cipher]. According to http://e2e.ti.com/support/arm/sitara_arm/f/791/p/156983/658334 link cfb is supported in am335x. I ...
20
votes
4answers
33k views

Google Chrome “Your connection to website is encrypted with obsolete cryptography”

Google Chrome is showing new information in the certificate section. Is this a big deal? If so how can I fix it on the server end? EDIT: Thanks for the answers but I'm not skilled in cryptography ...
16
votes
4answers
3k views

Is it dangerous to publicly share ciphertext?

Alice wants to share a message with Bob, but Alice and Bob can never be in the same place at the same time. We can assume they both know each others public keys (or agreed on a shared key, if that ...
2
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3answers
586 views

Simple string comparisons not secure against timing attacks [duplicate]

As I learned in a comment for How to encrypt in PHP, properly?, I was told using a string comparison like the following in PHP is susceptible to timing attacks. So it should not be used to compare two ...
0
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1answer
141 views

How can I tell if my client has been infected with CryptoWall?

Today a client ran a file they believed to be something else, they said a black window appeared, so I checked the code to see what it ran in CMD, but can't quite work out what it's doing. I've just ...
0
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1answer
181 views

Can you recover the password from ZipCrypto encrypted ZIP file?

I know that "legacy ZIP-crypto" is not secure and you can get at the contents of the file quite easily. Now the question is, can you also get at the password (assume this is a very long, very high ...
2
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1answer
265 views

Does OpenSSH use export ciphers?

With all of this talk of 'FREAK', no one has mentioned OpenSSH. It implements libraries from OpenSSL (until recently, anyway). Why aren't people talking about this? is there even a way to configure ...
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4answers
418 views

How to check randomness of random number generators?

Assume that I have a smart card that returns an 8 byte (for example) random value on reception of a command. The question is that: How I can check if this value is really random? (I don't have any ...
1
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1answer
107 views

How to keep a reasonable level of entropy in an encrypted file?

Encrypted (or random) data, by nature exhibit a high entropy value and non unencrypted data will exhibit a low entropy value. From an attacker point of view the precense of this high entropy value in ...
1
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1answer
46 views

ssl+symmetric with my own encryption algorithm? [closed]

I am a final year student currently doing my project, the title is "Mitigating man in the middle attacks using ssl+symmetric key algorithm". I would like to create my own encryption algorithm. I need ...
3
votes
2answers
319 views

Can this modified 'Many' Time Pad be made 'stronger' by using an extrememly long key?

Starting with a one time pad say you want to encrypt some small strings like the words in this sentence but you want to reuse the same OTP key for each string so that when you encounter the same word ...
1
vote
1answer
51 views

Using a Cryptovariable with an API Designed for Human-Generated Passwords

I'm working with a vendor who provides an API with a user registration method clearly designed for human-generated passwords. We're calling the API in an offline server-to-server fashion, however, ...
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votes
1answer
32 views

combining imperfect random number generators for shuffling an array

Shuffling an array to create a random stream for encryption is well known. The weakness is in the security of the random number generator that performs the shuffling. But is it true or likely that the ...
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votes
1answer
48 views

Do we need to same PGP version for decryption [closed]

Requirement: In our company Location A uses PGP encryption and sending data over internet. In Location B, we have to decrypt the file. Question is what do we require in Location B Do we need to ...
3
votes
1answer
90 views

Does PKCS #7 (CMS) add assurance to an email if a CRL/OCSP response is included, then revoked?

Suppose I issue a signing certificate in January, and have a daily CRL issued (expires in 1 day) to verify the validity of that signature. Then sometime in July I need to revoke that certificate. My ...
2
votes
1answer
79 views

Is TLS enough to prevent eavesdropping? [duplicate]

Is it enough to use only SSL/TLS for client-server application with authentication, registration and data transmission (like chat)? If it is not what I also need to use?
3
votes
1answer
118 views

Security of hybrid encryption scheme

I want to use a hybrid encryption scheme for file encryption. The scheme must use PKCS#1 v1.5 – which is vulerable to padding oracle attacks – because many smartcards (e.g. the OpenPGP Card) only ...
3
votes
1answer
374 views

SIM card - Cryptography

I would like to have general infos about crypto and commom SIM card in mobile phone(I know there may be different implementations, technos according to the operator...). Is crypto used only for ...
3
votes
1answer
144 views

Has the security of PuTTY been examined?

I am wondering how PuTTY stacks up against other SSH implementations with respect to scrutiny and security of its SSH2 protocol implementation. PuTTY is probably the most-used SSH client on the ...
-2
votes
1answer
80 views

Tell type of encryption if given both input and output strings [closed]

I have the string Thisisatest that is encoded as MDQ4MGFhMzRhYTNkYjM1OGIzN2NkZTJhYjZiNjUzMjY= and I am trying to find out what encryption is used here. I think that the encoded string is base64 ...
0
votes
1answer
97 views

What is the security/copy protection model for streaming media services?

I realize this is a broad question, but maybe there is a simple answer From my understanding, Streaming media services such as Amazon instant video, Netflix, and others do all decryption client side. ...
1
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1answer
83 views

Why should I have my GPG key expire? [duplicate]

When creating a key pair using gpg it asks me for an expiration date: $ gpg --gen-key Please specify how long the key should be valid. 0 = key does not expire <n> = key expires ...
1
vote
2answers
75 views

Two-way encryption that can be nested?

In building a security system, I'm looking to prevent 'man-in-the-middle' attacks in a two-way encryption system, using the following setup: A sends B a message, encrypted with code 1 B sends it ...
7
votes
4answers
985 views

What happens when encrypting with private key? [duplicate]

I have a theoretical question. There is a public key-system. Person1 wants to privately send a message to person2. From my understanding, person1 is supposed to encrypt their message with public key. ...
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0answers
78 views

Questions about SRP algorithm

I trying to use SRP algorithm but I have some questions: Is that a good choice to use for registration and authorization SRP algorithm with SSL/TLS? And for all other transmission using just ...
2
votes
1answer
62 views

What does a FIPS validation certificate cover? Just software version or OS and hardware too?

As I understand it, if you want to be FIPS-compliant you have to use FIPS-certified components. My question is how different can your use of the component by from what's on the component's validation ...
0
votes
2answers
137 views

Why use anything other than RSA for transmission encryption?

Being fairly new to the cryptography and data security space, I have sampled a few "Introduction to cryptography" sites/textbooks and they all seem to start in the same general way: This is a Caesar ...
0
votes
1answer
64 views

Default Encryption - A Panacea or Placebo

I wrote this on LinkedIn - Discrete Discretion My first question is: Is it accurate to say that default encryption is a placebo? Will default decryption only make end-users think they are secure ...
2
votes
2answers
112 views

How can I create my own public certificate using openssl?

I have a public key/private key pair i generated using two primes p and q. I now need to use openssl to sign and create the certificate. I heard req utility and wrote this from the man pages. openssl ...
1
vote
2answers
145 views

What type of encoding do .pem files use to store the key?

What encoding is the modulus in RSA cryptography stored as in a .pem file? Is it something similar to base64 of the modulus? I can retrieve the modulus using the following: openssl rsa -in ...
2
votes
2answers
154 views

RSA and AES combination in offline situation

I need to securely request and receive data from a server. The client has the RSA public key, and the server has the RSA private key. So I am generating a random key for AES-128/CBC cipher and ...
3
votes
2answers
398 views

What is the point of AES key wrap (with JSON Web Encryption)?

I'm looking at JSON Web Encryption (JWE) and am left a bit confused about why you would use AES key wrapping. The document even talks about using matching key algorithm strengths: Algorithms of ...
14
votes
6answers
2k views

What are the differences between an encryption seed and salt?

Today I had a hard time explaining the difference to a friend. I know seeds are used when generating "random" strings. And salts are used when providing different outcomes to a hash. What is a ...
19
votes
1answer
554 views

How to encrypt in PHP, properly?

How do I encrypt data in PHP, properly, using symmetric-key encryption? I have a message M and a secret S. I'm looking for a solution that uses cryptography properly without making any of the usual ...
8
votes
3answers
44k views

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 ...
12
votes
1answer
956 views

Relationship between RSA, Diffie-Hellman Key Exchange, PKI and X.509?

I am getting confused with RSA, Diffie-Hellman Key Exchange, PKI and X.509v3. I took a look of RSA's mathematics algorithm, it seems like a encryption algorithm, right? Generating public key and ...
0
votes
1answer
40 views

length of a session key in EC?

In elliptic curve cryptography what should be the length of session key? Is there a specific metric to choose one, or are they randomly generated? I was studying one paper about defence against a ...
11
votes
0answers
478 views

Strength and length of Symmetric vs Asymmetric keys [duplicate]

There are many questions surrounding the differences between symmetric and asymmetric encryption keys. I think I've read them all at this point. But I'm still left wondering: Why does a "secure" ...
-4
votes
1answer
143 views

AES 256 bit key to plaintext conversion? [closed]

I'm a little rusty on cryptography, but I have successfully acquired a 256 bit key that is used for encryption and I want to know if it is possible to reverse it into its corresponding plain text ...
0
votes
0answers
28 views

TLS fallback when only one protocol is enabled

Consider I have IE with ONLY TLS 1.2 enabled. TLS 1.0 and 1.1 are disabled. (And SSLv2,v3) I have a server that only supports TLS1.2, with 1.0 and 1.1 disabled as well. Assuming they share a ...
2
votes
0answers
63 views

Offering a privacy scenario with PHP mcrypt library

first of all, sorry if my question is not clear, because English is not my first language. Anyway, let-me explain the concept I'm struggling to solve as the best solution. I have some guys, and they ...
0
votes
1answer
56 views

How to save a web page with its certificate?

I've made a payment to an online store and they're claiming there's no order with the number that appeared in my screen, therefore they're refusing to send me the product. I still have the page opened ...
23
votes
5answers
5k views

Never spell a word the same way twice?

A long time ago I was reading about Renaissance-era ciphers and I remembered this quote: David Kahn, author of The Codebreakers, quotes Giovanni Battista Porta who published, in 1563, a famous ...
0
votes
1answer
115 views

SSO software – where is symmetric key stored?

In SSO software (Oracle E-SSO …), I heard about (primary) key encrypting user’s credentials, but I can’t read anything about how this key is managed ? When using smartcard, I can understand that ...
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votes
2answers
90 views

Will cyber security be around forever? [closed]

As time goes on, won't computers be able to automatically test for vulnerabilities to the point where they will not be prevalent any more? What I'm essentially asking is will information security be ...
1
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0answers
87 views

Problem in understanding Blakley's Secret Sharing Scheme

I need to implement Blakley's Secret Sharing Scheme. I have read below mentioned two research papers but still unable to understand how to implement it. 1. Safeguarding cryptographic keys 2. Two ...
0
votes
1answer
394 views

How does LSARPC protocol work?

I'm trying to understand how does the LSARPC protocol work internally. In particular, I would like to know how secured is it. I couldn't find anything in the internet or in different books.
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2answers
484 views

Generating authentication token from PHP sessions

I have a traditional PHP site which uses sessions. I've developed a real-time app in nodejs and wish to authenticate users here based on their PHP session. The procedure would go something like this: ...
0
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1answer
59 views

Is it possible to perform one-way OTR MITM?

Here's something that is bugging me recently: suppose that me and my friend establish an OTR session and - as a result of that - DH key exchange is performed. My friend verifies my key, but I cannot ...