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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SAM and SYSTEM file copying to another PC

Can I copy a SAM file and a SYSTEM file of a laptop and just change my SAM file and SYSTEM file on my own PC? Will my PC then have the password of the laptop? Or is there another way I can copy the ...
2
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2answers
395 views

linux hidden OS

I have been reading about hidden volume OS with truecrypt, and now with its successor, VeraCrypt. https://veracrypt.codeplex.com/wikipage?title=VeraCrypt%20Hidden%20Operating%20System But Couldn't ...
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16answers
9k views

Ensure that a file can only be decrypted after a specific date

Are there any cryptographic schemes/protocols that would allow me to encrypt a file, make it publicly available, but ensure that it can only be decrypted after specific date? I assume it would be ...
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1answer
181 views

Crack 512-bit RSA encrypted messages without a private key?

I was wondering if it would be possible to crack a message that was encrypted with 512-bit PCKS1 encryption with the public key. I am doing a project for our science fair type thing at school and have ...
2
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1answer
482 views

IKEv2 vs OpenVPN

I want to ask you for information about the IKEv2 protocol for a VPN connection. I haven't found so much information on the web. I am interested especially regarding the usage on a mobile phone. Is it ...
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1answer
26 views

RC4 encrypt many messages with same password

I would like to ask if it's insecure to encrypt many different messages sent over the Internet encrypted by RC4 with the same password. If it is insecure, then if I encrypt the first message with the ...
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2answers
115 views

Encrypting unique fields in a Database

I'm still a beginner to cryptography and want to know what the best practice is for solving the following problem: I'm creating an application with the requirement that a user's email address must be ...
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3answers
243 views

Why do I have to use multiple keys for each direction and purpose?

I'm currently writing an examen about 'Lessons Learned in the IT-Security'. I already found some thing, which shouldn't be done. But right now I'm in trouble finding the reasons why not to do so. ...
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2answers
685 views

How the NSA can break trillions of encrypted Web and VPN connections

Based on Diffie-Hellman's negotiation of key exchange, why would it turn out that only a few primes are commonly used? What and who determines the prime? Would it not be safer to use a safe prime? ...
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2answers
136 views

Saving Authentication Tokens to Third-Party Websites

So Flickr allows you to authenticate users to your app via app_key and secret and returns an authentication token. I want to securely save that authentication token in my database, but also be able to ...
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3answers
165 views

What stopping someone from offering distributed and encrypted email? Just like Bitcoins

Basically Email service that is ran over a network, so it's not owned by any one entity. Everyone can use it and send email to someone else. All messages travel through a web of interconnected ...
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2answers
92 views

Encrypt DB Fields preserving search functionality

I would like to protect sensitive information stored on a Postgresql database, but I would not like to encrypt it all. The idea is to encrypt only those fields which hold sensitive information. I was ...
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2answers
109 views

Snoopers Charter VPN advice needed

With the Snoopers Charter coming soon in the UK, I intend to start using a VPN service. Disregarding issues of the VPN logging user details or leaving my IP address discoverable, what other potential ...
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2answers
223 views

PHP processing form submission, how can I best protect sensitive information submitted via the form?

I am using PHP 5.6 on Apache 2.4 I have a form that will collect sensitive information about the user that need to be encrypted. My current solution grabs the sensitive information from the POST and ...
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6answers
3k views

Do spaces in a passphrase really add any more security/entropy?

I often see passphrase suggestions written as a sentence, with spaces. In that format are they more susceptible to a dictionary attack because each word is on it's own as opposed to a large unbroken ...
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3answers
2k views

How secure is 7z encryption?

I have a text file in which I store all my bank details. I compress and encrypt it with 7-Zip using the following parameters: Compression parameters: Archive format: 7z Compression level: ...
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2answers
2k 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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4answers
14k views

How (in)secure is POP/IMAP/SMTP

I'm making a few assumptions about basic email security, and I want to confirm or clarify some of these points to make sure I understand the big picture. Please correct me where I'm mistaken: The ...
4
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1answer
76 views

Can a FIDO U2F device be used for symmetric encryption?

As I understand, U2F is mainly used for authentication. It uses challenge-response scheme to check if the device used for logging in is the same device which was used during registration based on ...
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0answers
34 views

How many bits of security is in a n-bit modulus?

In a paper that I read, "A riddle wrapped in an enigma" by N. Koblitz and A.J. Menezes, there are several statements like this one(at page 4, section 2.3): ..., the NSA updated to Suite B [40] so ...
3
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1answer
106 views

Encrypt/sign a client-to-API request?

We are building a JSON API on top of our Ruby on Rails Web application, using JSONAPI::Resources to expose endpoints and Doorkeeper to handle user authentication. Most of our API endpoints will be ...
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2answers
93 views

Internet browsing encryption

I have a shared wifi point with a person who might be interested in knowing what I am browsing, writing and downloading in the internet. This person is the master of this wifi network, only he has an ...
2
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1answer
237 views

Browsers and export regs. Is SGC still valid?

I was reading a rather dated book on SSL/TLS, which mentions International Step Up certificates and Microsoft's Server Gated Certificates which were the way around the US export rules for economic ...
2
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1answer
102 views

iOS encryption and performance

iOS file encryption deploys many layers of encryption; There is the AES-256 accelerator encrypting general flash memory with the per-file-, UID-, and GID keys. There is Data Protection on the software ...
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1answer
100 views

Dragnet TEMPEST Surveillance?

Just something I considered recently -- TEMPEST attacks are pretty well known; basically you intercept EM leaks from a computer to discover compromising information (i.e. encryption keys, what's being ...
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0answers
36 views

Is there a point in cascade encryption? [duplicate]

I was reading the other day about some programs (ex: DiskCryptor), and with my limited knowledge of cryptography.. I started wondering about cascading encryptions (ex: AES-Twofish-Blowfish). Assuming ...
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3answers
239 views

Using a stolen certificate on a server

Yesterday I asked the following question regarding what would happen if you placed a stolen certificate on your own server and edited the 'host' file so that the DNS name matched: Could a stolen ...
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0answers
21 views

How to securely send your user and hashed password to a server? [duplicate]

I'm making a user system for an app I'm developing, and I have a client side (the mobile app itself) and a server side (where the database remains) for it. The app sends get and post petitions to the ...
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2answers
67 views

How to forge custom IEEE 802.11 packets?

I read about 802.11 networks and found out that all the frames from client are directed to the AP. How can I forge IEEE 802.11 packets so that I can send them directly to the clients using the group ...
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2answers
115 views

RSA: Do private keys have to be private?

I was thinking about using RSA, but in reverse. Where everyone has the private key, and only the server has the public key, so that all the clients can decrypt a message from the server, and the only ...
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1answer
62 views

Encryption that service provider themselves cannot decrypt?

I recently saw the following message verbatim on an online application I use. The login is simply a login/password combination. There is no oauth, no two factor authentication, etc... This sounds ...
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2answers
84 views

Should I worry if I have tried to ssh into a 'fake' dyndns.org site? (with ssh keys)

I often ssh into servers for work and play using dynamic dns with ssh keys that are password protected. Twice now (shame on me!) I have mistyped the dyndns.org part of the address and been greeted ...
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3answers
340 views

Prevent or detect key copy

This question can be classified as somewhat two interrelated questions - or two goals. Main aim is basically to authenticate client to server, but remain secure even if someone steals the key from ...
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2answers
64 views

Public key - private key question

I have a query about public/private key encryption that I hope someone can answer. So as I understand it: Client connects to server and server responds with certificate Client pulls the public key ...
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1answer
131 views

How do programs like keepass protect their data even when it's loaded into RAM?

After noticing the feature in Keeppass having the option to "Enable in memory protection" I began wondering, how can memory be encrypted and still be useful? Without going into homomorphic ...
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5answers
9k views

Encrypting All Network Traffic

For a corporate network, is there a way to possibly encrypt all network traffic on the local network? I would like to ensure that there is nothing left for chance to be packet sniffed. Not even ...
3
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0answers
61 views

Is ECB secure if I can guarantee that I never encrypt the same block twice?

After reading about modes of operation for block ciphers, I've found that basically all discussions about ECB end with: "never use ECB". For example this security stachexchange answer. However my ...
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1answer
299 views

Any small idea to decode this algorithm from PHP script [closed]

So I think the algorithm is based on the php function ENCODING_decode defined in includes/encoding.php (which i don't have) . The encoded result $xId_campaign_encoded from the php script has ...
2
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1answer
347 views

How is an ODBC connection encrypted?

Most conversations about ODBC are Microsoft centric, but the protocol is often used in heterogeneous environements, such as a Windows client connecting to a database on an *nix server. While my ...
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2answers
1k views

Improving stateless REST API authentication token - or ditch it for database persistence?

I'm looking to implement stateless REST authentication into an API. I've been reading up on articles here, and have implemented an idea that works, but I was hoping to get some feedback on its ...
5
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1answer
59 views

Dynamically decrypting files

Is it possible to store (video) files encrypted (using AES or similar) in the cloud and have clients' browsers download those files and dynamically decrypt them to start viewing them whilst they are ...
2
votes
1answer
43 views

Why aren't mixed-content connections allowed on localhost?

Recently I had to redo something at work. It involved a servlet on Tomcat that accepted requests from external users (Connection A), which in turn connected via SOAP to a Web Service on the same box ...
45
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4answers
22k views

ECDSA vs ECDH vs Ed25519 vs Curve25519

Among the ECC algorithms available in openSSH (ECDH, ECDSA, Ed25519, Curve25519), which offers the best level of security, and (ideally) why?
2
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2answers
137 views

Encryption of Google's Android apps

Does Google use network encryption on it's Android apps like Gmail, Drive, Google Play, Docs, and others when doing authentication/data transfer? What type of encryption is it? Is it secure? I have ...
0
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1answer
55 views

Passcode and encryption

Does a passcode encrypt data on a device? Do additional steps need to be taken in order to encrypt the device, even when a passcode is already set? Or does having a passcode mean the data is ...
2
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3answers
57 views

Stacking Encryptions (Stream over Block)

I am reviewing the code for a product our team developed where credit card information is stored in a local database in the event of no internet connection and came across the encryption methods. The ...
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1answer
74 views

Safe to store encrypted data with (password protected) pfx file

I have created a self signed certificate using Powershell's New-SelfSignedCertificate, with the intention of encrypting and storing a username / password in public. Specifically using - ...
3
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3answers
212 views

Reading encrypted data before sent to remote server

I'm developing a mobile app (Android only for now) to provide a disposable e-mail service to users. Users will be given temporary e-mail addresses so they can receive and read e-mails for a certain ...
36
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5answers
22k views

How do I verify that WhatsApp is using end-to-end encryption?

Slightly old news: Whatsapp Just Switched on End-to-End Encryption for Hundreds of Millions of Users Is there any test that I can perform to verify that WhatsApp is indeed using end-to-end encryption ...
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0answers
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E2E Encrypted group calls and messaging (plug'n'play solution) [closed]

I'm looking for something similar to Skype I guess. Here are the important main features that I need: Easy "plug'n'play"-like solution (like Skype for example) Safe end to end encryption for calls ...