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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2
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0answers
9 views

hash function notations and existing cryptographic hash algorithms

I am implementing Role-based access control by referencing the paper Enforcing Role-Based Access Control for Secure Data Storage in the Cloud. In page 6, they have mentioned to choose hash functions ...
-1
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0answers
41 views

Encrypt a file with Block Cipher in CBC mode [on hold]

I have using Crypto++ Library for encrypting files, and use of AES Standard and CBC encryption mode. i know comparison between Block Cipher and Stream Ciphers and Operations of each modes, so i want ...
0
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1answer
36 views

Which of AES modes are safer and faster for transferring data over the network?

I have using Crypto++ in Qt and use of AES Algorithm for encrypting files. I know about AES modes and their applications. I have use of StreamTransformation method for encrypting files in CBC and EAX ...
1
vote
0answers
22 views

Recommended Crypto Security Setup (Implemented Algorithms)?

Firstly I'm not a crypto expert, however I know how to use algorithms that other people have defined before in practical usages, that is, as long as they live up to their promises. The thing is that ...
72
votes
13answers
6k views

VP of IT claims he unhashed 100% of all 16k employees' PWs. Is he lying to us?

I work for a company which has ~16,000 employees. Periodically, our VP of IT sends out a newsletter with "tech-tips" and misc IT stuff. The topic of this week's newsletter was "password security". ...
11
votes
3answers
3k views

Additional security of keyfile on top of a master password for KeePass

I use KeePass + Dropbox to manage and synchronize my passwords across my devices. This system works really great and I trust KeePass' security model. However my biggest remaining concern is the ...
2
votes
1answer
31 views

Android N - Security Crypto Provider is deprecated

As mentioned in "android developer's blog" , http://android-developers.blogspot.in/2016/06/security-crypto-provider-deprecated-in.html , security Crypto provider is deprecated on Android N. And also ...
1
vote
2answers
48 views

Does a hash of a 32-bit integer make a better hash salt than the integer itself?

I have a scenario where I already have a table of resource passwords stored as unsalted 128-bit hashes. I'm unable to force owners to provide new passwords, so I'm trying to mitigate the situation by ...
7
votes
1answer
32 views

Does the use of a smartphone's Secure Element really offer security benefits to a banking app?

My bank's Android application allows users to perform financial transactions without the use of the physical token generator (which requires an ATM card to be inserted and a valid PIN to be provided) ...
4
votes
2answers
61 views

Is CHAP authentication still secure?

Assuming the use of the default hashing algorithm MD5, is CHAP authentication still secure? I appreciate that MD5 is considered broken in terms of collision resistance, but I also understand that in ...
1
vote
1answer
326 views

Bypass SSL Certificate Pinning using SSL Vulnerablilities

I am wondering if it could be possible to sort of "bypass" the certificate pinning protection of Android or iOS using for example the POODLE SSL vulnerability. According to this blog Entry it is ...
9
votes
3answers
13k views

How are “security levels” of identities in TeamSpeak 3 implemented?

TeamSpeak 3 VoIP communication system uses a concept of so called identities to identify the client to the server. These identities are basically public/private key pairs. In order to prevent people ...
5
votes
3answers
1k views

How would you know a certificate/private key if you extracted it from RAM? Or would you?

Related to, of course, the heartbleed vulnerability, I've been reading the news about the worst case scenario for this attack being the extraction of the SSL private key, because, of course, this ...
2
votes
2answers
152 views

number of ciphertext-plaintext pairs needed in double encryption

So I know in single encryption you would simply require at least 1 pair of plaintext-ciphertext, to carry out an exhaustive key search; you continue trying different keys until one is found that ...
17
votes
2answers
4k views

Does my PGP key really need to match the e-mail address for which I'll be using it?

In considering whether or not I want to join the big web o' trust and put my keys on a key server, I got to thinking about how it would affect my e-mail address' exposure. I generally try to keep my ...
3
votes
0answers
48 views

security of libgcrypt when cross-compiling for windows?

Looking at libgcrypt, specifically secmem.c it seems that it does not account for windows-specific memory handling (e.g. VirtualLock) and in fact there is a very troubling comment: #elif defined (...
-1
votes
2answers
132 views

How long would it take to generate a file to match a hash? [duplicate]

A individual file only has a single hash of any specific byte length. But an individual hash can represent a large number of different files. Given a 256 byte hash, how long would it take to ...
11
votes
5answers
2k views

Hashcash, is this really used?

I just heard about this term, is it really used? The concept does not seem new, is it used and/or implemented in current technologies?
0
votes
1answer
48 views

X509 / SSL certificates in practise

After learning the theory behind cryptography I'm having quite some problems understanding how SSL or X509 certificates works in practise and I simply cannot find useful information in the internet. ...
4
votes
3answers
522 views

It is safe to buy a domain if I get this message in Firefox?

I want to buy a domain name from a big registar (well known on the internet) but when I go to checkout I see that my link is going from full encrypted to “Connection Partially Encrypted” and I am ...
1
vote
1answer
173 views

Partial decryption using untrusted decryption service

While there are ways to encrypt and decrypt information, most of these seem quite computation-heavy. Because of this I am thinking about splitting decryption into two parts - one is computation heavy ...
0
votes
2answers
36 views

Can an RSA signature be changed given the public key?

If I were to post on a forum (with potentially malicious administrators) my public RSA key and a small string of text that was signed with the corresponding private key, could someone with access to ...
123
votes
6answers
46k views

Password Hashing add salt + pepper or is salt enough?

Please Note: I'm aware that the proper method for secure password storage hashing is either scrypt or bcrypt. This question isn't for implementation in actual software, it's for my own understanding. ...
-4
votes
0answers
33 views

Can somone proivde me with armv7-based or armv8-based implemented cryptography algorithms [closed]

Recently,My professor ask me to implement some cryptography algorithms(RSA,DES,AES,RC4,Rc5,etc).Although I have some knowledge about assembly language, I have no idea for these cryptography algorithms....
0
votes
2answers
117 views

I want to encrypt certain entries in a database. Is this a good plan?

I'm working on a web app and want to offer the users the option to "encrypt" their account. This wouldn't encrypt everything related to them in the database. Just certain critical fields. I've ...
-3
votes
4answers
203 views

Roll your own encryption - with a twist

I am familiar with Schneier's Law: Any person can invent a security system so clever that he or she can't imagine a way of breaking it. I have read the many posts on this exchange littered with ...
20
votes
4answers
18k views

Whats the difference between MAC vs hash

What is the difference between the two algorithms? One difference that I know of, is that MAC is keyed and hash is not.
0
votes
0answers
26 views

ISO 9564 Approved Encryption Algorithms for PIN, why symmetric block ciphers?

I am currently researching best practices in designing a potential PIN management solution for a financial services application and began looking into ISO 9564 as a source of requirements. One of the ...
835
votes
23answers
166k views

XKCD #936: Short complex password, or long dictionary passphrase?

How accurate is this XKCD comic from August 10, 2011? I've always been an advocate of long rather than complex passwords, but most security people (at least the ones that I've talked to) are ...
19
votes
6answers
29k views

Why is WPA Enterprise more secure than WPA2?

In personal mode WPA2 is more secure than WPA. However, I have read that WPA Enterprise provides stronger security than WPA2 and I am unsure exactly how this is achieved.
38
votes
7answers
5k views

Exploiting MD5 vulnerability in this PHP form?

I've been practicing in security-related topics and I came upon this problem which I don't understand at all. You receive a form with one input named pass, and this is the code you need to bypass: &...
6
votes
2answers
1k views

Why is using a pseudo-random key considered more practical than a one-time pad?

I am experiencing confusion regarding one-time pads. I have read that a one-time pad generates a key that has the same length as the plaintext. This is considered to be an overhead in sharing such a ...
0
votes
0answers
27 views

How to determine which form of encryption is used? [duplicate]

I have an application which is developed using classis asp. The password is encrypted in the following format - LHFJOJ1234 Can anyone tell me which format is this? I don't have the source code. So ...
1
vote
1answer
82 views

Multi hash security [duplicate]

Is md5(sha1(pass)) more secure than md5(pass)? For example in case of sqli when an attacker can't get our hashing schema, brute force or dictionary attack would be much less efficient. Am I right or ...
1
vote
2answers
71 views

Detecting a Crypted executable that is supposed to bypass antivirus [closed]

I've seen many Crypters being advertised to bypass antivirus and they work. The malware crypted by the Crypter evades antivirus detection. How would you programtically or using a tool reliably ...
6
votes
2answers
686 views

Requiring 2 keys to access a content

I need to use an external service that can only be accessed by password. I don't like the idea of storing the plaintext password on the server, but AFAIK there's not much I can do. Considering this ...
2
votes
1answer
108 views

Can an attacker make in-app-purchases of my products in their app?

My iOS app needs to store a pre-shared secret. It cannot embedded within the App Bundle itself because it could be extracted by statically analysing the bundle. Apple's In-App-Purchase system allows ...
0
votes
1answer
52 views

How does (Py)NaCl work exactly?

At the moment, I deal with PyNaCl (Docs) and have a question about it: My situation is that I want to create a server that interacts with clients. Both the server and the client will have a long-term ...
0
votes
4answers
195 views

Which layer of OSI model does end-to-end encryption and decryption happen in a network? Why?

I thought it happens at Layer 6, but some resources state that it happens at either Layer 3 or 4.
1
vote
3answers
219 views

Why don't the majority of today's malware use strong cryptography?

While reading another story of botnet takedown, my wondering has reached its apogee: Why don't malware authors use cryptography (encryption + signing) provided by good libraries when their creations ...
1
vote
0answers
19 views

Substitution Table in TKIP

In TKIP Encapsulation, we divided the per packet key mixing process into two phases. In phase 1, we are taking three inputs i.e temporal key (128-bit session key), transmitter MAC address (48 bits) ...
0
votes
0answers
43 views

Choosing Key and IV in AES-256

I am working on a real-life project for a firm. I have to encrypt data using AES 256 as per specification. I want to know how are the key and IV are really chosen in real world projects. /dev/urandom ...
0
votes
2answers
91 views

C# .Net most secure way to store RSA Key Pair in Windows

At the moment I am looking into the most secure way to store a private RSA key on Windows. Making it as much usable for the end user as possible, while keeping the security to its highest. As this ...
2
votes
1answer
225 views

Encrypting data before sending to SaaS tool and decrypting on browser view

I'd like to send data to a SaaS tool, where the data is stored in the cloud. I'll use Google Analytics as an example, but it applies to any similar service. Google Analytics does not allow you to ...
-1
votes
1answer
34 views

Question how PPP with CHAP for Cisco works

I'm learning to configure a simple PPP link with CHAP authentication for two Cisco routers. I'm trying to make sense of how router makes sense of the configuration in this example, as the logic of ...
55
votes
5answers
174k views

How can I export my private key from a Java Keytool keystore?

I would like to export my private key from a Java Keytool keystore, so I can use it with openssl. How can I do that?
1
vote
1answer
56 views

Securing confidential information between users

I know there are several issues about encryption, but my case is slightly different Users have confidential information stored on their device They have a RSA key pair The information must be ...
5
votes
3answers
5k views

Shared Secret, is it a public key or a private key?

Reading the Diffie-Hellman non mathematical explanation i found that some mathematical operations are performed on private-key and the recipient's public key to generate a "shared secret" on both ends ...