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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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
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2answers
35 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 ...
2
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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 ...
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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
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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 ...
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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 ...
1
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1answer
46 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 ...
0
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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 ...
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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 ...
1
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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 ...
2
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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
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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 ...
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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 ...
0
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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 ...
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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: ...
1
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1answer
218 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 ...
1
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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 ...
0
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2answers
511 views

Security of several files all using same password/key (7zip, AES256)

I'm working on a simple secure mirror for potentially untrusted services like Dropbox, Owncloud and so on. (Current code may be seen here: http://www.codeduce.com/extra/secure_mercurial) Currently ...
2
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2answers
146 views

Obstacle in Implementing a Time Limited/Number of Use Limited Software

How does one implement a trial period in a product properly, e.g. a trial period that lasts 30 days, or limits the number of product uses to 10? Storing the entries, even in an encrypted form, isn't ...
0
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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
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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
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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
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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 ...
3
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2answers
167 views

How do web email clients store my passwords from other providers?

The situation comes down to this: When I enter in hotmail, it retrieves my messages connecting to other providers: they could only do so by using my email and password. Since I had signed in a ...
1
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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 ...
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2answers
476 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 ...
1
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1answer
128 views

How does Bitlocker only-PIN method work?

Microsoft explained USB-key and TPM based BitLocker decryption process on this article. USB-Key process: The steps in the illustrated sequence are as follows: 1- The operating system starts ...
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1answer
112 views

Android support for TLS 1.1

Do anybody know from what version of Android did TLS 1.1 started to be supported directly by the OpenSSL version preinstalled in the system?
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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 ...
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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 ...
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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 ...
5
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1answer
81 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 ...
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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 ...
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3answers
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Is 7-Zip's AES encryption just as secure as TrueCrypt's version?

The main difference being TrueCrypt creates containers and 7-Zip encrypts the file itself, so file sizes can be guessed. Now let's just talk about the strength and breakability of the encryption. ...
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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 ...
2
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2answers
3k views

How do you bruteforce decrypt data if you don't know what you are looking for?

If I wanted to brute-force decrypt data, I would try decrypting it with a key and see if the decryption returned nonsense. If the decryption returned meaningful data (ex. something that a natural ...
1
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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 - ...
2
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3answers
141 views

Adding photos to Truecrypted, airgapped laptop from camera safely

I have a Truecrypted, airgapped (no internet connectivity at all) laptop that I use as a completely secure computer for sensitive files. I want to add images from my iPhone (I know), camera or other ...
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1answer
76 views

I want to encrypt content on USB or SD Card [closed]

I want to encrypt the content on a USB or SD card that can only be decrypted by an app installed on any device or TV. When the USB is not connected to that particular app, it should not be accessible. ...
1
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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
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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 ...
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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 ...
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votes
0answers
52 views

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

EUAXXKAARKBRHMWQUPEWBLKGWQXXUOQPMNDWRRUIEUNWUNXXWMTLIEZYBPRYENZBTRXXZZ ...
4
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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 ...
0
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1answer
148 views

Hipaa Compliant Server

I have an instance in Amazon EC2 and need to be HIPAA compliant. I have two questions, Should I need to do a block level encryption of the database storage. Should I need to encrypt sensitive data ...
1
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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 ...
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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?
0
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2answers
124 views

Using different algorithms to slow down GPU password cracking

I have some job related files I have already compressed with 7Z. I have protected each with good 10 character passwords consisting of upper, and lower cases, numbers and special characters. And I ...
3
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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 ...
37
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2answers
17k views

How secure is Ubuntu's default full-disk encryption?

How secure is the encryption offered by ubuntu (using the disk utility)? What algorithm is used underneath it? If someone could at least provide a link to some documentation or article regarding that ...