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

learn more… | top users | synonyms

0
votes
2answers
22 views

What's the benefit of hybrid cryptosystem vs asymmetric for small data blocks?

It's a common belief hybrid cryptosystems are better than asymmetric only. Is that allways like that? What's the benefit of using symmetric and asymmetric encryption for small data blocks (< 100 ...
2
votes
2answers
34 views

How do I encrypt external drive with Password which is compatible with both Linux and Windows?

I wanted to encrypt my external drive with password, which is compatible in both Linux and Windows. Truecrypt is an option. But the development of it is stopped few months back. I came across ...
0
votes
0answers
18 views

Establish IPSEC Tunnel between two Ubuntu 12.04 PCs over LAN [migrated]

I have two ubuntu 12.04 32 Bit PCs between which I want IPSec Tunnel to be setup. I have setup ipsec in both systems and ipsec verify runs fine on both. Since I have no prior experience of openswan, I ...
0
votes
1answer
34 views

Can the aproximated date on which a given Encryption Algorithm will become prone to brute force be predicted?

I have a very elementary understanding about encryption so this question may have false assumptions, Lets take an encryption algorithm that is impractical to break through bruteforce with today's ...
-5
votes
1answer
37 views

Requirment for encryption algorithem to be secure/safe [on hold]

When we call encryption algorithem safe/secure? I can list following: is not possible to find key from cipher text is not possible to find plain text from cipher text Resistant to brute-force ...
0
votes
1answer
57 views

How will Gmail be able to detect SPAM and display ads when emails are encrypted end-to-end?

Context Google is making end-to-end encryption easier to use. SPAM How will they be able to perform SPAM detection when the email is transmitted and stored encryptedly? I suppose that if the SPAM ...
4
votes
3answers
229 views

Security Implications of using Base64 Encoding with Encryption

Are there any security implications of converting a byte-array encryption key into a Base64 string before use? I am creating a generic encryption helper for a project, and for the sake of consistency ...
2
votes
3answers
37 views

Encryption while logged in

If I'm using full disk encryption on my home computer, and it's online, are the hard drive contents encrypted when I'm logged in and using the machine (from the perspective of an online attacker - no ...
-1
votes
0answers
38 views

How to determine possible encryption type of a given data [duplicate]

I have a encrypted data which consist of 2 numbers: A random number of form 0.110134486415522 This number is always less than 1 and is generated at start of every session encrypted numerical ...
-1
votes
1answer
38 views

Permutation based file secure

I have a thought. 1. Take a file. 2. Read number of bytes. If its less than 2048, padd it till 2048 3. Read each byte. And create a single file which contains the particular byte. Give a random name ...
1
vote
1answer
39 views

Is it safe to use private key encryption for lots of small blocks of data themselves?

I currently handle small JSONs of sensitive information which are guaranteed to be smaller than 100 bytes. You can encrypt up to ~500 bytes with a 4096 RSA key. Is it safe/secure to store these ...
0
votes
1answer
51 views

How negative are virtual machines (vms) to /dev/urandom?

I looked at the questions here and here. This then piqued my interest as I've recently been involved with looking into FIPS compliance, and in my vm environment /dev/urandom compliance testing ...
-3
votes
0answers
51 views

Trouble identifying a has [on hold]

So I have this hash: +VZyZlAHP6HAgoaPBrBz with a known plaintext value being 378734493671000. For the life of me I cant figure out what kind of hash this is. I have 2 others I need to decrypt as well: ...
0
votes
1answer
46 views

Is Lock-a-Folder a secure and reliable way to encrypt information?

What are the properties of Lock-a-folder? does it create plain-text temporary files anywhere? (e.g. ntfs artifacts, etc) does it allow running a program from the folder as if it was a normal folder? ...
1
vote
1answer
45 views

Decrypt signature file based on plaintext

I have 2 text files used by an application. One is a very large "schema" array (approaching 100,000 lines, JSON format). The other is a .txt.sig file generated somehow from the contents of the schema ...
1
vote
1answer
60 views

Hardware Implementation of Encryption Algorithm

In the abstract of the AES-GCM RFC, the following passage is prominently included: [AES-GCM] can be efficiently implemented in hardware for speeds of 10 gigabits per second and above... Is the ...
1
vote
1answer
44 views

Can Cipher Suites defined in TLSv1.2 be negotiated by clients that only support TLSv1.0?

If my server has only the cipher suites enabled which are defined by TLSv1.2 does that force a client to also use TLSv1.2 or else not be able to connect or can the connection fallback to TLSv1.1 or ...
1
vote
2answers
32 views

PKI expired and renewed, do my correspondents have to do anything?

My PKI certificate (Digital ID for email from Symantec, issuer is "VeriSign Client External Certification Authority - G3") expired after 1 year and so I have renewed it. Do the people I correspond ...
3
votes
1answer
83 views

Hardware encrypted external HDDs

I'm planning to buy an external HDD with hardware encryption, namingly the WD My Passport Ultra 2TB. On the WD website the information about the encryption is sadly scarce so I'm asking here. How ...
1
vote
0answers
50 views

Database row level encryption scheme

I am wanting to secure some highly sensitive data in a database. This would mean that the data needs to be encrypted and remain secure for 100 years if it were to fall into adversary hands. I also ...
1
vote
2answers
475 views

Why is VeraCrypt more secure than TrueCrypt?

TrueCrypt retired with a mysterious "Using TrueCrypt is not secure as it may contain unfixed security issues" (source) Yesterday Slashdot reported VeraCrypt as a better replacement (source) since it ...
0
votes
0answers
46 views

Replacement for TrueCrypt on Linux supporting multiple ciphers [closed]

I've been using TrueCrypt for some time now, but as it is discontinued I'm looking for a replacement that will provide equivalent security. I know the usual suggestion is to use LUKS, but as far as ...
1
vote
0answers
23 views

Can Diffie-Hellman be scaled up or force-multiplied? [migrated]

I'm not too familiar with the math involved with the exchange of keys, I've read it over several times, but math isn't my strong point. My understanding is that smart people are hard at work to ...
8
votes
4answers
714 views

Why the symmetric key is added to the message?

Yesterday in my class we learnt how to send a message from Alice to Bob with the achieved goals of confidentiality, integrity and authenticity. In order to have a better performance we use a hybrid ...
1
vote
0answers
45 views

Is an anonymity network like Tor viable on top of the GPG web of trust?

The web of trust is a graph where the vertices are GPG users (actually, their keys) and the edges are cross-signatures. If we put issues of owner trust aside and assume that all participants only sign ...
0
votes
0answers
19 views

Protect file with digital signature that can be verified using public key

Sorry if the answer is obvious, I am really new to this stuff. I need protect a file from changing using public-key cryptography. The file should look like this: Filecontent ...
1
vote
1answer
55 views

is this data encryption scheme viable?

My goal is to be able to encrypt the data so that no one would be able to make use of it if it was stolen. User data - the one that will be encrypted - can be any type of data Data encryption key - ...
1
vote
1answer
27 views

Difference between sshv1 and 1.5?

I've been searching for the answer to this but haven't had much luck. What is the difference between SSH version 1 and 1.5? Is 1.5 a release of 1? As in 1.2, 1.3, 1.4, 1.5? Are there any ...
3
votes
0answers
35 views

Linux, TRESOR and XTS

I want to switch from using LUKS for full disk encryption to TRESOR. TRESOR tries to prevent cold boot attacks by storing the encryption key in the CPU's registers. It uses the kernel's crypto API for ...
-1
votes
0answers
12 views

Best way to encrypt system command output based on user? [closed]

I am developing a Web application where users can run a specific system command and wait for the output. The output should be only visible to the specific user (not a big problem) and I want to make ...
-6
votes
0answers
52 views

What is the encryption of these two codes I've posted below? [closed]

EUAXXKAARKBRHMWQUPEWBLKGWQXXUOQPMNDWRRUIEUNWUNXXWMTLIEZYBPRYENZBTRXXZZ ...
-3
votes
0answers
80 views

What's the best free encryption alternative after Trucrypt has been discontinued? [closed]

I've been reading about a couple of promising TrueCrypt forks (VeraCrytp and CipherShed). Is there anything else you would recommend? Or which one to choose among the two?
1
vote
1answer
36 views

Flawed understanding of SQL Server Transparent Data Encryption (TDE)

We host a database for one of our applications on Microsoft SQL Azure. One of our clients was dissatisfied with the fact that TDE is not supported on SQL Azure (and the database is otherwise not ...
4
votes
2answers
123 views

Encrypt with private and decrypt with public

Above picture is captured from iOS Security overview at page 25. The path encrypt with public and decrypt with private makes sense. But the other path, encrypt with private and decrypt with public ...
2
votes
3answers
27 views

Do passphrases need to be run through PBKDF2? Almost impossible to brute force?

Passphrases normally contain more data then passwords and can provide more entropy. It seems like it would still be hard to brute force a passphrase w/o using PBKDF2, assuming a user didn't select a ...
3
votes
2answers
112 views

Would it be possible to create a zero knowledge social network?

I understand the concept behind a zero knowledge web application where only the user has access to their data. What about a social network where some circles of user have access to that data? Is it ...
3
votes
0answers
16 views

Serpent 256bit key wrong round keys [migrated]

Assume that we have this 256bit key: 15FC0D48 D7F8199C BE399183 4D96F327 10000000 00000000 00000000 On first 0-7 keys we can't apply formula wi=(wi-8 xor wi-5 xor wi-3 xor wi-1 xor phi xor ...
6
votes
1answer
119 views

Two takes on PHP two way encryption - which one is preferable?

I need to encrypt some data and have it decrypted on a later point in time. The data is tied to specific users. I've gathered two possible solutions... 1: The first one is derived from the official ...
1
vote
1answer
51 views

Problem with common factor in RSA [duplicate]

In the RSA key generation steps, what if two entities select a common factor to generate n (i.e. p*q1=n1 and p*q2=n2) resulting in gcd(n1,n2) <> 1 ? This will lead to a problem that everyone ...
5
votes
1answer
80 views

Secure Boot on Microsoft Surface Pro 3 (or modern PCs)?

Got a Surface Pro 3 today (it's awesome BTW!) and noticed in it's EFI that it's got TPM enabled, "Secure Boot" enabled (unsure what such an umbrella/catch all term actually covers) And then in ...
1
vote
1answer
42 views

Is it safe to store important data in an encrypted access token?

Is it safe to store important data in an encrypted access token? For example, instead of storing access tokens in a database, not storing them at all and putting their associated data into them before ...
1
vote
1answer
35 views

Securing an OAuth / OpenID Connect identity in a cookie for easy login

I have a website that uses Azure Active Directory or Google+ for logging in. I go through an OAuth2 login flow, and the users email along with their tokens are returned to me by their identity ...
0
votes
2answers
71 views

PCI Compliance - Encrypted Mobile Apps

My company (health care) went through a PCI audit and needs to solve some major issues. Our branches collect CHD on paper and saves them to a network drive as a pdf that our corp office accesses to ...
0
votes
2answers
133 views

With RSA, can one ensure that two entities will not have the same private key?

With the RSA encryption algorithm, is there any guarantee that two different entities will not be given the same private keys?
0
votes
0answers
19 views

FEAL-4 Fk Function 4 Rounds [migrated]

As I understood in FEAL-4 it needs 4 pair of round keys. Which means that we need to launch Fk function 4 times, but the problem occures on the 2nd round. At first round we have original 64 bits key ...
2
votes
2answers
76 views

Securing commands

For a project I'm working on, I need to securely send commands between servers. These commands should not be able to be altered, and there should be some security about not being able to just keep ...
0
votes
3answers
115 views

Can you have Secure encryption with a backdoor, and still be secure?

Is it possible to have an encryption algorithm/implementation that has a "backdoor", that also wouldn't introduce flaws into the encryption? For instance, if you have a master password, once that ...
-1
votes
3answers
61 views

Can AES encryption prevent modifying bits in a wireless protocol?

I'm building an application with NFC which is a wireless communication protocol. An attacker can modify bits in a wireless communication protocol. I want to prevent this. I know we can't prevent an ...
3
votes
2answers
82 views

Key Size vs. Block Size: In Practice

I've seen a lot of confusion between encryption key size and block size. I feel like I completely understand the difference between the two, no need to explain what they are. But it's when put in ...
1
vote
1answer
97 views

Secure backup on online Cloudstorage

i own a small private server (@home) with all necessary features for my backup purposes (Owncloud, SVN, GIT). My target now is to ensure the safety of my data in emergency cases like fire/flood. For ...