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

1
vote
2answers
63 views

Encrypting a huffman encoded file

I wrote a huffman encoding program that can compress and decompress files. The file contains a header which contains information that allows me to retrieve the huffman tree. I wanted to add a simple ...
2
votes
2answers
632 views

Can Cryptolocker (Or Other Ransomware) Encrypt Files That Are Already Encrypted?

If you have already encrypted files, are they still vulnerable to being encrypted a second time by a program like Cryptolocker, or would this protect them?
17
votes
5answers
1k views

Why is security through obscurity not a good option for encryption? [duplicate]

I feel like there must be a simple explanation, but I've been looking around haven't found any wholesome answers. Take for example my name is Alice and my best friend Bob and we want to communicate ...
-2
votes
1answer
392 views

Is AES more secure than Rijndael? [closed]

Which algorithm is generally considered to be more secure, and is AES-192/AES-256 still considered to be secure? After reading this it's lead me to belive that the Rijndael algorithm would be a more ...
-2
votes
2answers
127 views

Is this adaptation of using a One Time Pad safe?

For example, lets say there are two people named, Bob, and Jim. Bob wants to send Jim a long secret message, and he decides to use a OTP to encrypt his message. Both Bob and Jim know a secret ...
4
votes
1answer
104 views

Car Remote App Security

Car manufactures like BMW, Audi or Mercedes-Benz all provide mobile applications to control your car. All apps share really critical functions like remote lock/unlock or the ability to find your car ...
2
votes
1answer
114 views

Is it possible to design a system where the client doesn't have to trust the server?

When you are using services like chat, file sending, exchanging etc., you always have to trust server providing these services. The only way to use services without having to trust third party is to ...
1
vote
1answer
58 views

Save application autostart login token on computer

I need to login desktop application while autostart on server (like skype does). What is the best practice to save authentication token (password)? Should I use something like RSA encryption (which ...
-3
votes
1answer
28 views

Which encryption technique should be used for users name and passwords in my notebook [duplicate]

i writing all my passwords and users names on my notebook emails,amazons,facebook. and i have really Nosy little's brothers that will probably look at my notebook when i am not around, which ...
1
vote
2answers
74 views

Which encryption technique should be used for cloud computing data transfer?

I want to setup my application for cloud computing for Software as a Service. There is going to be a lot of data transfer between my server and client, to and fro. The technique I have envisaged is: ...
-2
votes
0answers
35 views

What type of encoding/encryption is this? [on hold]

Im new to encoding and this realm, and I know this is not Base64. Could anyone tell me what this is? ·H AGHü§“-GYÖÍ=cp:S´’u@Ô∂ıAº¨¿mÇ…VÙ®ù¯˘JÂK‚“][ÿ ∞4‹ ...
7
votes
1answer
247 views

Collision attacks on OCB?

I've been looking into the OCB cipher mode and everything I hear sounds good. I was planning on implementing it. Everything except for this lone voice, that is: Collision attacks on OCB: We ...
13
votes
3answers
5k views

Are phone calls on a GSM network encrypted?

When I make a call on my cellphone (on a GSM network), is it encrypted?
6
votes
1answer
191 views

How could a system be zero-knowledge?

I'm actually interested about zero-knowledge storage system. Those system where the storage provider claims he can't have any access to the data stored. As far I know, the data are encrypted using a ...
15
votes
8answers
5k views

Is TrueCrypt safe enough to store clear-text-passwords?

The reason: I want to be able to use a portable USB drive to access my passwords on any machine and OS. TrueCrypt seems to be the only program that has sufficient support on all major platforms. So I ...
0
votes
1answer
50 views

Securing user postal address in a database?

I've been assigned a web project that deals with shipping goods between two parties. I am unsure what a secure database scheme (if any) would be for storing the recipient's postal address and whether ...
0
votes
1answer
31 views

Forward Secrecy not supported with referenced browsers?

I am running a scan against one of our servers from the Qualys SSL tester site and it says that my server "does not support forward secrecy with the referenced browsers". What exactly does that mean? ...
48
votes
6answers
13k views

Can my IT department read my Google Hangouts chats while at work?

Is Google hangouts encrypted? Would my work's IT guys be able see pictures and text I send while on a work computer? Yes I know I shouldn't be sending stuff I don't want them to see while at work, but ...
1
vote
1answer
96 views

Klein and PTW wep attack

I'm working on an implementation of Klein's wep attack. For that, I've set up a router with wep encryption and collected 50,000 unique IVs from it. I tried only calculating K[0], meaning - the first ...
2
votes
1answer
59 views

How does Mylar ensure encrypted data remains secure even if the live app code is compromised

Because Mylar does the decryption in the browser, the key is never stored on the server. Nice. This moves the threat to the browser, where, if the attacker is able to get a malicious script to be ...
2
votes
2answers
129 views

How can I secure the secret key?

I am a bit confused about securing the secret encyption key. Here is the scenario: I need to encrypt some data (file) This data will be read by a program (say written in C/C++). Both the program ...
0
votes
1answer
26 views

encrypted lookup-keys for key-value store

I'd like to use a key-value store (cassandra, redis, ...), but I don't trust the server. The clients have a shared secret, and I'm using that to encrypt the stored values. But what is the proper way ...
2
votes
2answers
175 views

Using a TPM with Linux

I have the need for a company laptop (Dell e6540) that contains our java application on it to go out for evaluation purposes. For this reason I would like to make sure that the HDD is protected from ...
15
votes
4answers
2k views

In what ways does Full or Partial Homomorphic Encryption benefit the cloud?

Can someone explain, in plain English, the practical ways FHE and PHE can be leveraged in the cloud? Some interesting (and confusing) links include this Microsoft Research PDF and this wiki entry. ...
1
vote
1answer
21 views

updatedb and encrypted home folders: Does it store unencrypted file and folder names somewhere?

When you encrypt your home folder in Ubuntu and Debian, it protects not only the file contents but also the file and folder names. Yet I see that updatedb and locate works in Debian. When I run ...
-5
votes
0answers
54 views

text messages you cant delete [closed]

why is there an anonymous text on my phone that will not delete?
0
votes
0answers
20 views

Possible CPA or CCA attack when using AES-CBC mode under the following situation?

Both client and server know a shared key in advance. Both sides us EVP_BytesToKey() derive a pair of same key and same IV. Then, client and server start transferring data encrypted by AES-CBC mode ...
0
votes
1answer
38 views

iOS Security/Encryption techniques for REST webservice [closed]

Say there's a banking app with a lots of web-service calls involved. How do you store secure data (such as sessions, fund transfer validation keys etc) encrypted locally which can be retrieved back ...
-1
votes
1answer
76 views

PCI compliant transparent data encryption at disk/folder level on Windows?

Is there a way to achieve PCI compliant data encryption at disk/folder level in Windows in a way that is transparent to applications(they must be able to write/read to encrypted folders/disks as if ...
1
vote
3answers
330 views

Protect database data from everyone, including sys admins, etc

One of the things that has always bothered me about simple database data encryption: If the server is compromised, the database is effectively compromised. The attacker can use the same code as the ...
2
votes
2answers
221 views

Easiest solution for automatic encryption of files on Dropbox?

I don't trust Dropbox to keep my files secure. In fact, the same goes for all the other file clouds. What I'd like is a easy and cross platform means of encrypting files that I add and read from ...
1
vote
2answers
139 views

Is a Diffie Hellman Ephemeral key good material for being used as a symmetric cipher algorithm key?

I am designing a secure protocol (for academic/learning purposes) and I am at the point where I need to (re)design the key exchange step. In my previous implementation, I used to rely on RSA to ...
2
votes
2answers
117 views

How can I secure my api to avoid copying?

Im building an app which should receive data from my server. The Api should be a PHP based script which provides the data as JSON. However I want to keep the data private and it should only be ...
0
votes
1answer
56 views

Encrypting folders with flash drive key?

Is there any way to have a flash drive encrypted and it will only open with one computer that has the key in it?
0
votes
0answers
42 views

Are temporary files an issue when opening and editing an encrypted 7z file?

I am new to security and encryption. I want to store important information like passwords and pin codes so I don't forget them. So far I have been using LastPass but I would prefer a solution I ...
12
votes
5answers
1k views

Securing a laptop against attacks (article)

I came across this article when looking for ways of hardening my laptop, and this guide seemed extremely thorough. It is perhaps overly paranoid, but it will be good to have a guide I can trust should ...
2
votes
1answer
157 views

Are there HIPAA requirements to encrypt our database hosted in AWS

I'm developing Medical Billing & EHR Software. On completion we are planning to use AWS for hosting and thus provide SAAS. Do we need to encrypt the MySQL database in order to keep HIPAA ...
1
vote
1answer
180 views

Making a bitcoin-like secure mail protocol, how to tackle public keys?

I'm making a new mail protocol (probably already exists, but I've learnt a lot of things about security and privacy on the way). Here's the summary(much simpler if you know bitcoin's inner workings): ...
0
votes
1answer
46 views

How are TLSv1.0 ciphers negotiated as TLSv1.2?

I'm a little confused about something I am reading in Bulletproof SSL. "TLS 1.2 is the only protocol that allows suites to define their PRFs. This means that for the suites defined before TLS 1.2 ...
2
votes
2answers
190 views

Why doesn't Bitlocker mix the password with stored key?

Bitlocker doesn't support USB key + PIN (password). The reasoning was "the password is too weak to provide additional security". Isn't that flawed? With a USB key and password, I've got some level of ...
4
votes
2answers
408 views

How to implement client side encryption for CalDav & CardDav content?

I'm looking for a client-side encryption implementation that would be able to secure CardDav & CalDav data so that they couldn't be compromised even by the hosting provider. Server side: PHP or ...
0
votes
3answers
162 views

Java AES encryption output length

I am trying to encrypt few database columns (string values) using Java AES algorithm. This is to protect certain sensitive data. For some users these data should decrypted. In Java AES encryption, if ...
0
votes
0answers
21 views

Encryption test failed [migrated]

I am facing a problem when attempting to send an encrypted email via Enigmail (Thunderbird) in Ubuntu 14.04. I was following the Email Self-Defense guide https://emailselfdefense.fsf.org/en/ ...
1
vote
2answers
68 views

Are digital signature algorithms subject to the same types of attack as public-key encryption algorithms?

I understand that digital signatures are usually implemented by encrypting a message digest with a private key, decrypting the resulting signature with a public key, and verifying that the message ...
24
votes
4answers
13k views

What steps do Gmail, Yahoo! Mail, and Hotmail take to prevent eavesdropping on email?

I would like to ask what happens when an email is sent from gmail, yahoo or hotmail public web email services? I don't understand email protocols in details, but as far as I know email traffic is ...
0
votes
2answers
50 views

ECDSA ciphers and forward secrecy question about key exchange

I have heard that with forward secrecy that the ECDSA ciphers generate different keys for "each session" because they are not dependent on the private key of the server. My question is how is "each ...
2
votes
1answer
142 views

Is encrypting something more than once safer than hashing more than once?

I am aware of the implications that hashing something more than once correctly will increase the security of a system, but doing it incorrectly will decrease it, as noted here and on various other ...
2
votes
1answer
39 views

Possibility of using CA as an attack point by governmental organizations under their pressure

I was always concerned about the model of trust behind CA stuff we use . Well, for most of us, it is OK to trust them, since they are reliable organizations with a bunch of solid experience. ...
1
vote
1answer
93 views

Security margin of a winzip, Winrar password of 64 characters against GPU cracking

what s the longterm security margin of of a winzip or Winrar file encrypted with aes-256 and a password consisting of 64 completely random characters set a-z 0-9 and other printable special ...
4
votes
2answers
962 views

Extract AES key by comparing plaintext and encrypted data

Is there a kind of analysis which would enable me to get AES key which was used for encrypting arbitrary data while I have both original and encrypted version of data ? The problem is that the AES ...