Tagged Questions

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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1answer
40 views

How can I hide proprietary elements of test data in tests that are automatically run?

I am writing automated tests for a web application that will be run periodically over night, and I am running into a moderate security issue. In order to make the tests thorough, I am hoping to ...
1
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1answer
66 views

Mapping of plaintext and ciphertext in DES

The plain text and the cipher text have a one to one mapping. Given a pair of those, can there be multiple keys used to generate the same pair? Or can a particular plain text - cipher text mapping be ...
1
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1answer
98 views

Chat encryption system avoiding protocol sniffing and then key+decryption replay?

I'm working on a chat system and I want to add it some kind of security (not just HTTPS with SSL since I've read it can be sniffed and decrypted with a few tools). Now, my knowledge in cryptography is ...
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1answer
92 views

How to decode/decrypt strings of text [closed]

So I'm trying to decrypt/decode some text strings. I don't believe they're hashes because they vary in length too much and the software they are used for is able to easily decode them and display them ...
3
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1answer
206 views

How resistant is the iPhone encryption against brute-force attacks?

I just read the following paragraph in an article from the New York Times about Apple encrypting iPhones by default): Breaking the code, according to an Apple technical guide, could take “more ...
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0answers
66 views

How do public/private keys work?

I have read "How does SSL/TLS work?" and "Public-key cryptography", and I know basically what happens when using a Public-key to encrypt/decrypt something. To sum up what I've read, A Public-key ...
0
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3answers
96 views

Is is necessary to encrypt the message digest?

In symmetric key settings, in order to provide the message integrity, we compute the hash of the message. The message along with the message digest is then encrypted. Is it necessary to encrypt the ...
1
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0answers
56 views

Secure self-concealing symmetric encryption (non-verifiable decryption)?

From what I observed using standard encryption tools such as OpenSSH and GPG, the decryption only succeeds when the correct password/key is provided (or at most a few others, in case of collision). ...
2
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2answers
135 views

Does a self-signed certificate offer more protection than a public key?

I'm having a hard time finding the practical benefits of transmitting a self-signed certificate over simply a public key. I understand that a self-signed certificate proves the integrity of the public ...
2
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3answers
94 views

AES Key Management / How To Swap Encryption Key

I'm currently using AES 256 for the encryption of my web application and the security policy context specifies that the encryption key must be replaced once every few months. When that happens what ...
1
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2answers
94 views

Does adding multiple recipients to an encrypted message decrease security?

Let's say you want to send the same GPG/OpenPGP encrypted message to 50+ recipients. Assuming everyone you send to is trusted, and there is no risk of any recipient leaking their secret key, is ...
0
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0answers
26 views

L2tp protocol security

do l2tp protocol is secure enough to use in unsafe home network ? protection from man in the middle ? i having a problems install openvpn in linux you think following that guide will offer me ...
3
votes
1answer
88 views

Does encrypting a setting in web.config actually provide security?

Does encrypting a value in the web.config file actually provide any real protection? It seems to me that any web app can read that setting. Yes that's more work than just reading the web.config file, ...
0
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2answers
184 views

What does 2^77.1 calls presented in a SHA1 attack mean?

Regarding the SHA 1 deprecation, I found this information here: http://blogs.technet.com/b/srd/archive/2013/11/12/security-advisory-2880823-recommendation-to-discontinue-use-of-sha-1.aspx I know ...
1
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1answer
45 views

Encrypt pdf by the server to prevent printing and copying

We are building a portal where users can upload few materials. we have been successful in using the command lines of linux to convert doc,ppts to pdf directly through the server but we are not able to ...
5
votes
3answers
615 views

Does Android encryption really prevent law enforcement access?

Google recently announced that in Android L encryption would be turned on by default: For over three years Android has offered encryption, and keys are not stored off of the device, so they ...
0
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2answers
121 views

Can we hide a constant hashed key used for AES encryption of a password?

Are there any methods in java to hide a constant hashed key which is embedded in a class? FYI, the key is used to AES encrypt a password used to authenticate a Web Service which would only take a ...
3
votes
2answers
62 views

Any advice on how to assure patients that a medical facility is well protected against identity theft?

My apologies if this question has been asked before. How does a medical practice assure patients that the practice follows excellent computer security practices? Conversely, how does a patient find ...
1
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1answer
110 views

Efficacy of self-made ransomware protection

I was recently wondering about how to circumvent malware such as the infamous Cryptolocker a while back and was wondering about the efficacy of having a set of files with known content in a known ...
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1answer
81 views

What is the algorithm of bcrypt? [closed]

In many places I heard that people recommend to use the bcrypt algorithm to save passwords into database while creating web applications.I want to know what is the algorithm used to bcrypt a password ...
2
votes
1answer
52 views

Is there any asymmetric scheme provides signature with length of 30 bytes?

I want to send short messages to cell phones.Commonly a short message is no longer than 70 bytes. I need 20 bytes or more holding information and the rest bytes are for signature provided by ...
13
votes
3answers
1k views

Trying to understand why signatures in root certs “are not used”?

Taken from here: Don't worry if the root certificate uses SHA1; signatures on roots are not used (and Chrome won't warn about them. Why are the signatures not used? Are not root certificates ...
0
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2answers
65 views

Is my Password Hashing Secure or not?

I have recently created a code for hashing password. Can you please give your advice over the security of my code? The function takes a password, then converts it to a number. #include <string> ...
0
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1answer
93 views

How can I safely include the encryption key in the encrypted file?

I am encrypting text files using AES256 (no particular reason, that can easily be changed). Before granting access to a file, I need to verify if a party knows the correct key, but without necessarily ...
17
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3answers
2k views

Is SHA1 weak for SSL?

I noticed that today after I scanned a site on the Qualys SSL Labs site that SSL ciphersuites which use SHA1 are now highlighted as being "Weak". It seems this has just happened; I scan sites pretty ...
0
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1answer
69 views

Privacy concerns while traveling with HDDs [duplicate]

I'm traveling to UK for college and I'm bringing 2x2TB drives with me. I'm concerned about my privacy when going through the border as they might search the drives. So I came up with the following ...
0
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1answer
79 views

Encrypting the salt with password [duplicate]

Salts are stored in the plain text and readily available with the hashed passwords if the password database is compromised. What if we encrypt the salt using password itself? Doesn't it make offline ...
2
votes
1answer
157 views

Python implementation of AES and SHA256/512 that are FIPS-140-2 validated?

For security purposes I need to use AES encryption and SHA256/512 in my Django/Python project. I know there are various libraries out there that provide different encryption methods but I can't seem ...
0
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2answers
137 views

What is actually the purpose of encrypting the values in a cookie?

I was researching on internet security. When I reached at section Cookies, I happened to read that the values inside a cookie are generally stored only after encrypting them. But an encryption can be ...
1
vote
1answer
151 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 ...
23
votes
3answers
2k views

Tell people that I can encrypt emails

I know that it is still not very easy to use PGP for an average user. However, the situation is improving (there are some easy plugins that can even nicely integrate into your GMail webmail). In ...
1
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1answer
159 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?
2
votes
1answer
72 views

Does mixing different types of encryption make the connection more secure?

Like when I browse a website using SSL from my laptop that is connected to my router using WPA2. My router talks to my ISP using IPSec. Is that more secure or these types of encryption have nothing ...
0
votes
2answers
117 views

How do I know that my connection is really encrypted?

I am using a VPN to ensure to encrypt my browsing. I wonder though if I could check somehow if the datastream really is encrypted?
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2answers
146 views

Opinions on my “Encryption at rest” implementation idea

Ok so basic overview of the environment I'm envisioning: Webapp w/ db backend storing sensitive data, possibly phi; standard user:pass auth due to unteachable users. My idea was to encrypt row data ...
1
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1answer
87 views

What network protocol is Crashplan using?

I have been using CrashPlan for a while internally (i.e. local backup server). I would also like to setup off-site backup but my experience is that I have to forward a port from the router sitting at ...
12
votes
2answers
571 views

How Does A Random Salt Work? [duplicate]

I don't understand how using a random salt for hashing passwords can work. Perhaps random salt refers to something other than hashing passwords? Here is my thought process: The salt is used to add ...
3
votes
2answers
81 views

Link Layer authenticated encryption vs authentication

Many security articles discuss about adding an extra layer of security at the link layer by either authenticating the data at the link layer authenticating and encrypting it. If we have ...
2
votes
1answer
161 views

Storing a user's password in a retrievable manner

I currently store my users passwords as PBKDF2 hashes, for the authentication part of my web application. Each user also has their own private key and public key (also stored in their user profile in ...
0
votes
1answer
381 views

Can eavesdropping be facilitated by injecting content that will be transmitted?

I was asked during a job interview the following question, to which I couldn't find an answer then, and this thing is still bothering me. I was hoping someone might know the answer here: Consider ...
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2answers
62 views

If TLS compression is not supported is a site still vulnerable to attacks such as BREACH?

I have read that BREACH was a side channel compression attack against TLS however focuses on HTTP response compression. If a site has disabled support for TLS compression does that still mean it can ...
5
votes
1answer
291 views

BitLocker Password Change

My team at work was recently working on encrypting some hard drives using Microsoft's BitLocker on Windows 7 hosts. The initial encryption for the 2TB drives took several hours to complete. This is ...
0
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2answers
91 views

mac adress encryption

I am a student of information technology and I am doing a project on avoiding MAC spoofing by using MAC encryption. My goal is to encrypt the MAC address inside the packet and send that packet to the ...
2
votes
1answer
115 views

How effective is Opera Mini's encryption? Can it hide activity on a WiFi network?

I'm curious since I discovered the nature of how browsing works in Opera Mini. A URL request is sent to Opera's servers, they download the page then compress it to lower bandwidth. They use a file ...
0
votes
1answer
63 views

Secure communication End-to-end with android and Server

I´m building a enterprise application and I need to create a secure communication between android and a server. What is the most secure way to do End-to-End communication? Should I use HTTPS or VPN? ...
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votes
1answer
114 views

Is there a benefit to encrypting a file multiple times? [duplicate]

If I had to store a text file with some confidential information on the cloud, would encrypting the file multiple times (say, 3) with different passwords using WinRAR (AES with a 256 bit key) provide ...
13
votes
3answers
5k 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?
18
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 ...
1
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3answers
130 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
1answer
134 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 ...