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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Which Instant Messaging services use or allow secure protocols, and what do those protocols cover?

We all know there's a myriad of Instant Messaging (IM) services out there. But, which of these services uses or permits protocols that actually secure your communications? For those that do, what ...
51
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6answers
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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 ...
19
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4answers
8k views

Are phone calls on a GSM network encrypted?

When I make a call on my cellphone (on a GSM network), is it encrypted?
18
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3answers
3k views

In PGP, why not just encrypt message with recipient's public key? Why the meta-encryption?

It's described very well by this diagram. It seems like the process used is convoluted and more round-about than it needs to be. Why is an intermediate random key generated for the payload's ...
11
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1answer
4k views

When using AES and CBC, is it necessary to keep the IV secret?

If I encrypt some data with a randomly generated Key and Initialization Vector, then store all three pieces of information in the same table row; is it necessary to encrypt the IV as well as the Key? ...
11
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3answers
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Using TPM with DMcrypt?

Is it possible to use TPM for storage of some private key? It's not a full-disk encryption , I want it to be compatible with existing LUKS, just add another key, and store it in the TPM.
13
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5answers
1k views

How should passwords be stored if they must be recoverable?

By "encrypting" passwords you are violating CWE-257: Storing Passwords in a Recoverable Format. But this is exactly what the French government wants. They want to be able to obtain the passwords of ...
8
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3answers
253 views

Securing an E-commerce site

I'm building a custom e-commerce site, and the user will input their credit card details on the site instead of being directed to the payment gateway's site. I'm confused as to what the critical ...
6
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1answer
5k views

Will double encryption increase the security of cipher vs bruteforce?

Assume I have a function encrypt(mes,key) where mes is the message, and key is the key. The length of key is 64 bits. Last but not least: assume the only way to crack my cipher is a brute-force ...
17
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2answers
914 views

Encryption and the “security time decay” of prior encrypted data

This question is on the assumption that any data once encrypted, may (eventually) be decrypted through Brute force (compute power/time) Exploits in the cryptography used Theft of private keys ...
14
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4answers
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Doubling up or cycling encryption algorithms

I've occasionally read the suggestion to enhance security by either doubling up on encryption algorithms (encrypt a message once with one algorithm, then encrypt the ciphertext again with a different ...
13
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3answers
1k views

How secure is aSSL (javascript)? Does it effectively mimic SSL?

Some of you may be familiar with the aSSL project, which uses AJAX/PHP to mimic the SSL protocol. It uses RSA 512 or 1024 for the keys, and AES for the actual data. It looks impressive to me in ...
13
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1answer
2k views

How would I implement “Broadcast Encryption”?

I have a stream that I want to encrypt for broadcast to 10,000 subscribers. I know I should encrypt this data using a symmetric key; and also intend that this symmetric key will be rotated every 30 ...
10
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5answers
16k views

Can Skype chat be protected from snooping? Are there safe alternatives?

I use Skype a lot. With all of my clients, staff, contractors and friends, however, the acquisition by Microsoft worries me, as two of my clients are direct MS competitors, and I often work on long ...
7
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5answers
2k views

How can one secure a password/key in source code [duplicate]

If there is a need for source code to have a password in it, how should this be secured? This is purely an example, but say there is an app that is using an API, and you don't want to expose ...
7
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3answers
6k views

When is it appropriate to SSL Encrypt Database connections?

Let's say I have a web server I setup, and then a database server. However, they are communicating locally and are behind firewall. In my opinion, no SSL is needed here right? The only time to use ...
3
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1answer
1k views

Is hardware based disk encryption more secure that software based?

As a spin-off of my question on "Advice on buying an encrypted disk" -- and in an effort to address the question "how is hardware based disk encryption better?" -- I've started a new question. My ...
2
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3answers
689 views

Are the encryptions “broken” with great computing power?

http://www.dwavesys.com/en/pressreleases.html#lm_2011 Lockheed Martin Corporation (NYSE: LMT) has entered into an agreement to purchase a quantum computing system from D-Wave Systems Inc. I'm ...
10
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2answers
1k views

How might the U.K. Government's proposed internet surveillance equipment “bypass” encryption?

http://www.channel4.com/news/black-boxes-to-monitor-all-internet-and-phone-data http://rt.com/news/uk-privacy-internet-freedom-186/ 'Black boxes' will be installed by internet services providers ...
7
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4answers
2k views

How effective is iPhone 3GS and 4 device-at-rest encryption?

My primary goal is to protect Activesync-based communication from being copied or stolen from an offline device. In that context how effective is iPhone 3GS and 4 encryption?
5
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1answer
2k views

Security of bcrypt/sha256 key used with AES to encrypt a file

I'm looking to encrypt files using secure hashing and encryption algorithms in Python. Having used bcrypt in the past, I decided to use it for my passphrase calculator, then pass the output through ...
11
votes
5answers
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Compute the AES-encryption key given the plaintext and its ciphertext?

I'm tasked with creating database tables in Oracle which contain encrypted strings (i.e., the columns are RAW). The strings are encrypted by the application (using AES, 128-bit key) and stored in ...
7
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1answer
2k 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 ...
5
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6answers
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Mysql - two-way encryption of sensitive data (email addresses) outside of Apache, PHP and MySQL

We store user email addresses in our database, like many other websites. While we do take pride in the security measures in place, sometimes "just enough" is just not enough. We've begun looking into ...
3
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1answer
701 views

Are there any holes in this security design?

This design is for transport security between a client and a server. I'm planning on using it for a cloud storage system. I would like it to be secure against you-know-who. I'm trying to prevent the ...
3
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1answer
1k views

Using GPG or PGP for symmetric database encryption/decryption in c#

I am looking to symmetrically encrypt/decrypt information in a database. This info consists of short pieces of information, which need to be individually encrypted when a specific method is called. I ...
2
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3answers
336 views

Without SSL, what vantage point does one need to MITM non-SSL'd HTTP?

OK, so there are two things here: being able to read the content of the requests and responses, and then being able to modify them. The former may depend on the latter, I'm not sure. But basically, ...
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2answers
285 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 ...
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2answers
735 views

How to tell what encryption is being used [closed]

How do you tell encryption algorithm used by reading its output? Here is the one I am trying to figure out Åbd$ý ...
19
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2answers
6k views

stronger encryption for SSH keys

I configured my server to encrypt user passwords using 500,000 rounds of SHA-512. The question is, how does the standard AES-128-CBC encrypted SSH private key stack up to that, provided the same (or ...
47
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17answers
3k views

Can we still provide confidentiality when cryptography is outlawed?

In certain jurisdictions, use of cryptography by the private sector is limited: e.g. there are reports that in the UAE and other countries not all of the encryption capabilities of the BlackBerry are ...
27
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3answers
4k views

Why can a Tor exit node decrypt data, but not the entry node?

Me -> Node A -> Node B -> Node C -> destination The documentation on Tor always states that only the exit node C can see plain text data. How is this possible without me talking to Node C ...
27
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1answer
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iOS Encryption Details

Following on from this question Does anyone have any details/resources on the technical specifics of how apple implement encryption on their iOS 4.x series devices? The Apple marketing material here, ...
14
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3answers
3k views

Computationally simple, lightweight replacement for SSL/TLS

Target hardware is a rather low-powered MCU (ARM Cortex-M3 @72MHz, with just about 64KB SRAM and 256KB flash), so walking the thin line here. My board does have ethernet, and I will eventually get ...
19
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2answers
11k views

Strength of WEP, WPA and WPA 2 PSK

I know there are three method for wifi security. What are the relative strengths of the password encryption in WEP, WPA and WPA2 PSK?
13
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2answers
938 views

Storing sensitive information securely

I know there have been a few questions about this already, but I just wanted to know if anyone can take a look at my design plans to see if there are any gaping security holes. I am in the process of ...
26
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2answers
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How can I check that my cookies are only sent over encrypted https and not http?

I read a blog post GitHub moves to SSL, but remains Firesheepable that claimed that cookies can be sent unencrypted over http even if the site is only using https. They write that a cookie should be ...
21
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8answers
3k views

Software that encrypts the data before deleting it

I am searching for a software that would encrypt data and then delete it (as opposed to just deleting or wiping). With that, even if the file is recovered, you still have to break the encryption to ...
13
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5answers
2k 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 ...
25
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3answers
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Which SSL/TLS ciphers can be considered secure?

The OpenSSL website provides a long list of different ciphers available for SSL and TLS. My question is, which of those ciphers can be considered secure nowadays. I am especially interested in HTTPS, ...
23
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7answers
3k views

Why Say IP Addresses Are Harmless?

Whenever I see someone on the internet ask the question, "Can someone find out my IP Address from my tweets/my tumblr/facebook posts/whatever else", the response I always see is, "Who cares! An IP ...
22
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6answers
1k views

How to secure a WiFi network?

What do I have to do to secure a WiFi network? Is there any best practices? I have been recommended to use WPA2 encryption on the router, is that enough? What can I do to improve the security even ...
18
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1answer
474 views

How to encrypt in PHP, properly?

How do I encrypt data in PHP, properly, using symmetric-key encryption? I have a message M and a secret S. I'm looking for a solution that uses cryptography properly without making any of the usual ...
21
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6answers
8k views

Is AES encrypting a password with itself more secure than SHA1?

This isn't really a practical question, but more a question of curiosity. I heard a CS professor recommend stepping up from md5ing passwords not to SHA1, but to AES encrypting the password using ...
13
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2answers
32k views

What are the differences between MD5, SHA and RSA?

MD5 tools output hexadecimal values. In the same manner, do SHA and RSA together produce a hexadecimal (or any other) output? What are the differences between the MD5, SHA and RSA algorithms?
8
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1answer
3k views

How does adding a random serial number improve a certificates' security?

This article says: "Finding collisions is a tricky process, since it requires you to muck with the bits of the public key embedded in the certificate (see this paper for more details). Also, ...
4
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11answers
4k views

Definitely safest password storage scheme?

I already asked this on StackOverflow but I was suggested this would be a better suited place and I found no way to "move" the question so I have to copy it. Believe, I know, there are hundreds ...
36
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9answers
18k views

Are powerline ethernet adapters inherently secure?

I have 2 Zyxel PLA407 powerline adapters. Router is downstairs connected to one adapter, other adapter is upstairs about 30 feet away connected to a desktop. I have a house, not an apartment or ...
16
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2answers
3k views

How does non-ephemeral Diffie-Hellman key exchange become compromised in SSL when the RSA private key is leaked?

From my understanding, one of the major reasons we recommend Diffie-Hellman Ephemeral (e.g. DHE or ECDHE) over non-ephemeral DH, for SSL / TLS, is that compromise of the RSA private key (i.e. private ...
15
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2answers
3k views

What's wrong with storing private keys in the cloud?

I know this sounds like a dumb question, but whats wrong with it? Assuming that all private data is encrypted (by the client) using PBE AES256, then is this scheme more vulerable than storing keys on ...