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

8
votes
1answer
15k views

Why so long to break 128-bit encryption?

I read that 128-bit encryption takes millions of years to break. But if I encrypt a file using say winzip that uses 128-bit encryption but the password I use is only one character long (for example ...
2
votes
1answer
1k views

Can active attacks really decrypt a particular AES-256, CBC, PKCS#7 encrypted file?

I recently found out that active attacks are a threat against AES-256, CBC mode, padded with PKCS#7 (the CBC mode in particular. I should supposedly change to EAX to guard against these attacks). ...
6
votes
2answers
482 views

How less secure is an encryption if we know something about the original data?

I have a number of files encrypted with a key derived from a password. In line with standard practice, I use a random salt and password and do many PBKDF2 iterations to obtain an encryption key and ...
2
votes
3answers
21k views

Recovering encrypted SD card after Android Factory Reset

I was using Active Sync on my Android Galaxy S2 and as a result it enforced encryption of the phone and SD card. Phone did a factory resync and now data on SD card is still encrypted. Is there a way ...
7
votes
1answer
2k views

Encrypting sensitive data in software and storing/decrypting it on a server

I have searched IT Security and Google for something similar to this, but wasn't able to find anything remotely related to what I'm doing. I'm developing software which has 2 parts - a C# program run ...
1
vote
1answer
462 views

PKCS#7 message constructed by our code, any weaknesses in the output?

We have this as the PKCS#7 encrypted message. We would like to open this up for review and analysis here, for people to poke holes. This sample is generated via test certificates and keys. The concern ...
0
votes
1answer
4k views

How does PKCS#7 padding work with AES-256, CBC mode?

I'm a bit confused with AES-256, CBC, and how it works with padding (PKCS#7). Whenever I encrypt data of multiples of 16 bytes (the block size), extra 16 bytes are always padded at the end. For ...
3
votes
6answers
1k views

How to “demonstrate” man-in-the-middle attack?

I'm TAing a particular course on system security. A specific example is transitting the password in plain text when developing a web application (as part of a class project). Over the years a bunch ...
5
votes
3answers
1k views

Are private keys generated by different software packages compatible?

I know that GnuPG follows the OpenPGP standard, but if I generate a public/private key pair using GnuPG and upload the public key to a key server, i.e. the one at MIT, or use it to sign files, ...
5
votes
5answers
35k views

Cracking CISCO ASA Passwords

I've got a copy of a Cisco ASA config and i want to crack the following example passwords I've got the following lines in the config ASA Version 8.4(2) ! hostname ciscoasa enable ...
3
votes
4answers
637 views

Is it safe to have the salt equal to IV?

If I'm using AES-256 CBC to encrypt, getting the 32 byte key using multiple iterations of the PBKDF2 function with a 16 byte salt, is it safe for me to let IV be equal to the salt? (Edit: The salt is ...
4
votes
2answers
3k views

File security when encrypting files directly with the openssl command / and what about SHA1 hashing password first?

I've been using this command to encrypt files for a while now: openssl aes-256-cbc -a -salt -in secrets.txt -out secrets.txt.enc Then I type in a password. Can someone tell me, roughly speaking, ...
1
vote
2answers
340 views

What is a better practice - RSA Encryption vs Windows authentication

I have two machines running windows OS with IIS and window OS with MS SQL. In the production web.config file I configure the IIS to use a user name and password when connecting to the DB and then I ...
0
votes
2answers
162 views

How can I encrypt something user provided without risk of the key being exposed?

So, let's say I have a theoretical service. User has some text they want to encrypt. They pass it to me, and I encrypt it. Then, only I should be able to decrypt it afterwards. Another kicker, it must ...
1
vote
2answers
104 views

How can I set up signed downloads?

Scenario I have a web server that authenticates and redirects from HTTP to HTTPS. Clients can then view available "downloads" in their account. I want to be able to sign these download links - as in, ...
1
vote
4answers
378 views

Strategies to store/remember very long password?

If future proof encryption is - in theory - possible it will require long password. What are some of the strategies for storing or remembering very long - in this case rarely used - password? For ...
6
votes
1answer
2k views

Is there cryptographic material in a phone's SIM card that can be used with RSA encryption?

Given that a smart card stores a private key that can't be extracted, it appears that a SIM card is similar to a smart card in these respects. I need to store (or use an existing) private key on a ...
6
votes
3answers
11k views

Encrypt data within mobile app and send to web service

I'm developing a mobile application for Android and iOs. What is best practice when it comes to data encryption within the mobile application which will be sent to a web service? Basically I will ...
3
votes
3answers
176 views

Is it safe to mix authentication methods?

Is it a good idea to "combine" authentication methods? Example we can use username/password method to authenticate a user from a server. What if we used this as a first authentication step to get ...
5
votes
1answer
3k views

Android / CyanogenMod encryption vs GNU/Linux

Hi I am trying to understand how encrypting an Android based phone works compared to a GNU/Linux host which relies on LUKS dm-crypt. Here is what I understand: Encrypted LVM on GNU/Linux is an ...
1
vote
1answer
326 views

AES encrypt secret key with plaintext

We need to be able to retrieve password. Hashing is one-way, we can't do that. So we ended up using AES. We want to know if the following schema is safe or not. I am only familiar with modulo PK ...
5
votes
2answers
1k views

Is it reasonable to prevent timing attacks by using fixed processing time

I have systems that perform cryptographic operations within a SSL/TLS tunnel. My concern is that I may leak timing information when encrypting, decrypting, or hashing. Part 1 Is it a good idea to ...
7
votes
2answers
9k views

is it possible to use smime in the webclient of gmail?

I could not find any options in the webinterface of Gmail. all I could find was a Firefox plugin to use SMIME with Gmail, but it seems to be outdated
8
votes
3answers
796 views

How practical/important is the Lucky Thirteen TLS attack?

I was reading this article which talks about a new attack against TLS being called Lucky Thirteen. It claims to allow repeatable MitM attacks against HTTPS connections. It's described as being fairly ...
0
votes
1answer
113 views

Auto encrypt chunks of content for backup, best practice?

I'm just curious and it's more like a mind game, I'm not into cryptography. How would one encrypt data that's constantly generated? Put the data automaticly into chunks encrypt the chunk and send it ...
1
vote
2answers
151 views

Need a time consuming symmetric encryption

I have a database with millions of entries, each entry encrypted with a (different) password. Normally, only one entry is needed at a time. If somebody steals the database, I want to make it hard for ...
3
votes
2answers
309 views

Securing Time Sensitive Data

I have a number of time sensitive, embargoed pieces of information that I need to distribute over the Internet and have received at a precise time. I'm currently dealing with the problem by uploading ...
5
votes
5answers
191 views

How to avoid to lose data encrypted because it was encrypted by no longer supported software?

How can I avoid losing data that is encrypted using methods that may become obsolete? I have valuable family records I wish to secure, so I plan to encrypt them before putting them in long-term ...
2
votes
1answer
335 views

Credit card data - sharing and storage [duplicate]

What is the industry standard for sharing credit card data between client (thin & thick) and server?
2
votes
0answers
221 views

Utility to hide several encrypted messages in single file [closed]

I am interested, are there existing utilities/projects under way devoted to combining encryption and steganography. I would like to - combine two or more messages, encrypted with separate ...
3
votes
5answers
1k views

Does a binary executable have to have some critical plain-text components?

When companies package binary executables, they are often encrypted, compressed, scrambled, and otherwise made so that your lazy hacker can't simply open the program up in Notepad++ and see the code. ...
2
votes
2answers
228 views

Slow down symetric encryption

I'm developing a program in Java. In one step data should be encrypted and exported in a file. As of now we are encrypting in AES-256 I want to slow down a possible brute force attack as much as ...
4
votes
1answer
313 views

Saved passwords (use case)

I have a program in which a user enters a password, and the user data is stored encrypted using AES-128. The data and passwords must be stored together. Both the data and the password are encrypted ...
-5
votes
1answer
484 views

Secure Web application Password vault/manager [duplicate]

I would like to build an open source online password vault which allows users to securely store their passwords, like Keepass or roboform, but where a user can access their passwords through a ...
0
votes
1answer
628 views

Determine hashing algorthim only with known input and output

Given the input: test A system generates the following output hash: 0x001F41B6A0534D3B851D69EFE6237F550100000010D5F4FC65E64BCFDBF2590212E4411C44942C6C734C00ACFE13B958DCAB3614 I do not know ...
4
votes
2answers
773 views

How to secure a truecrypt container allowing access with multiple SSH public keys?

I would like to create a TrueCrypt container which can be accessed by multiple people. The container itself can be stored anywhere, e.g. in a shared folder in Dropbox or Google Drive, ... I would ...
1
vote
1answer
1k views

Picking an encryption algorithm for auth tokens passed via AJAX

I'm looking for a low CPU intensive encryption algorithm, to pass around session authentication tokens. As an example: The user will login in to the website (via OAuth, whether by the site as ...
11
votes
1answer
1k views

How to study the packets sent by a keylogger

One of my friends runescape account got hacked through key-logger. He downloaded a runescape gold generator from a file sharing site and tried to use it. I have a strong doubt that it is a key-logger. ...
8
votes
3answers
2k views

Encrypting user data using password and forgot my password

I am planning to do a web application which stores a lot of personal stuff (info, photos...). And to give users a sense of protection, I want to encrypt the data before storing it to the database. ...
3
votes
1answer
1k views

How to make a secure key distribution scheme/protocol?

We are building a data processing platform on Amazon AWS. We are going to store sensitive data in the S3 (encrypted) and then the Amazon EC2 node is going to be utilized to process this data. We are ...
2
votes
1answer
1k views

How to secure or (Ensuring Integrity) of Web Data in transit and in store?

Consider (usual scenario) You own a Shopping Cart Website and hosted on Internet, now, your hosting company provides you database to store your data. If talking about security, we need it for: ...
7
votes
3answers
13k views

AES CBC padding when the message length is a multiple of the block size

Assuming that a 32-byte plaintext is encrypted by AES 128 CBC - is it mandatory to add 16-byte padding, according to the different padding schemes?
3
votes
4answers
729 views

Can an attacker reuse stolen SSL private key to recreate that domain on his server

Say my domain (https://example.com) SSL private key has been stolen and was not protected by a passphrase then. Can the attacker uses that key and certificate to host the same domain on different ...
0
votes
2answers
846 views

“Premium SSL” vs “Stanard SSL” certificates - Any reason why I would want a “Premium SSL”? [duplicate]

Possible Duplicate: What are the advantages of EV Certificate? besides the green URL bar and free security scan and whatnot. Our website does NOT accept any personal info other than email ...
4
votes
2answers
2k views

What are the differences between ssh generated keys(ssh-keygen) and OpenSSL keys (PEM)and what is more secure for ssh remote login?

I have learned there are 2 methods to make SSH remote login easier and secure , those are; ssh generated keys (using ssh-keygen)OpenSSH Keys PEM (.pem) keys usually generated with OpenSSL (Amazon ...
2
votes
2answers
134 views

Which hard disk encryptions schemes are tied to the original hardware?

When using a laptop, an encrypted HD/SSD can be an important security measure. However, laptops are prone to accidents (fluid spills, dropping on the floor, etc) that may mandate some or all of the ...
4
votes
2answers
790 views

How to correctly implement AES in a backup application

I am writing a back-up application which should have the feature of encrypting the back-up. It must encrypt file data, paths and filenames. The application is being written in C# (.NET). Target is ...
4
votes
3answers
361 views

Completely mimimise the possibility of my web hosting account being hacked

I've just moved web hosting providers and I want a fresh, secure start. To a certain extent, I don't mind what I have to do I'm just fed up my account being hacked or infected. I just wondered how to ...
4
votes
3answers
282 views

jasypt message integrity

I've been looking into ways to encrypt an authentication token that I need to pass from one site to another. Things i have learned so far are use a high level library. don't use ECB use a HMAC to ...
1
vote
3answers
428 views

RSS Feeds: restrict access

"We are a bunch of journalists and we share much of the information via e-mails. This has become tedious now. Hence we found out a way to share, by just having to share our private blog posts via ...