A hash algorithm is a function which takes a variable size input and produces a fixed size output. The algorithm tries to make it difficult to predict the output for a given input, find two inputs with the same output, or reconstruct the input from the output.

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What are the strenghts and weaknesses of Whirlpool Hashing Algorithm

I want to find out if the Whirlpool hashing algorithm have any weaknesses. There are quite a bit of articles explaining the strengths of this algorithm, but for some reason I cannot find any on its ...
0
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1answer
19 views

activate user account through email

I see a lot of people say to hash for the token on email verification when dealing with member registration. I am wondering, if the email token is only to activate the account and nothing else, ...
7
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5answers
1k views

Why is being able to login with capslock bad?

I recently discovered a service where the password was not case sensitive. I understand basic principles of encryption and hashing so I am a bit worried, is this service storing my password in plain ...
2
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2answers
101 views

MD5 brute force on a faulty hash?

MD5 for passwords is considered insecure due to the ability to brute force and pick up the result. But what if I change some characters of an MD5 hash and I keep a record of that change so that ...
3
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2answers
72 views

Is a random work factor an increase or decrease of security?

Assume you use a proven hashing algorithm, like bcrypt with a work factor of 10 or PBKDF2 with 10K iterations. Normally that's really secure already and would give enough security already for most ...
3
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3answers
273 views

Implications of hashing to UTF-8 in a cryptographic function

I know that most hash functions today use Base64 encoding for their functions, resulting in hashes that use a-Z and 0-9, and, sometimes, other special characters. This results in 62-76ish possible ...
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1answer
49 views

How do I get the password knowing part of it and the length [on hold]

I'm new to all this, I'm trying to use Hash Suite to find a password with a word + 2 numbers. I know what the word is but not the numbers but I also know the length of the passwords ... What do I have ...
0
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2answers
354 views

What current algorithms are considered (un)secure? [on hold]

With the new release of Windows 10, Microsoft has given .NET, Javascript and C++ developers a whole new bunch of options for cryptographic algorithms. Where as the old .NET code only allowed AES and ...
0
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1answer
71 views

what is the most secure hash for virus definition databases in 2015?

I have been told, if I wanted to create virus signatures from infected files to use for detection in the future, I should be careful as some of them are prone to collision attacks?
31
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4answers
5k views

How does a hacker know how many times a password was hashed?

I've been reading a lot of questions about security and hash functions on this site and others. I am not an expert, just a curious mind and in my understanding the more iterations used to hash a ...
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votes
2answers
53 views

Use of Nmap ssl/http md5 and SHA1 hashes

I have below stated result on of the system by map: 443/tcp open ssl/http Apache httpd 2.0.52 ((CentOS)) | http-methods: GET HEAD POST OPTIONS TRACE | Potentially risky methods: TRACE |_See ...
1
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1answer
236 views

Rainbow tables/hash tables versus WPA/WPA2

In Wi-Fi penetration testing, is it possible to use rainbow tables/hash tables on WPA/WPA2 networks? Is there an advantage of one over the other? Where would one get said tables or can they be ...
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2answers
76 views

What the most trustworthy way to demonstrate digital File Integrity?

I'm looking for ensure the integrity of uploaded files and demonstrate this integrity to a user. In my current scenario, a user sends multiple files in several different formats, these files are ...
1
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1answer
71 views

Hashing passwords in OpenLDAP

I've seen a few posts on the internet saying most people store user passwords in OpenLDAP using one of OpenLDAP's many, built-in hashing functions. But OpenLDAP itself recommends handing off password ...
-1
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0answers
75 views

PHP crypted or hashed string to decode

I have a problem for captcha solve in 3 days. This is crypted or hashed captcha cookie 55debbcf069c81440660431 23 characters long. I found last 10 character is 1440660431 timestamp. I think first 13 ...
3
votes
1answer
66 views

Can I safely and securely store hash(sessionId) in application logs?

I'm considering storing a hash of a user's session ID in our applications logs on each request. This would allow users sessions to be easily tracked back to actions in our logs. I understand that ...
9
votes
2answers
154 views

Can client-side hashing improve after-the-fact security in response to password leaks?

Several questions on this site address client-side password hashing, and none of them admit to any security benefit beyond protecting other sites the user might use the same password for. However, ...
5
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1answer
137 views

Random padding in hash functions

In this answer, it was recommended that you add random padding when hashing messages for a trusted timestamp, such as for predictions, in order to avoid dictionary and brute force attacks (at least ...
0
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1answer
34 views

Is there any problem using empty salts with PBDKF for this purpose?

The aim is to generate a secure key for symmetric encryption. I have a master password, from which I want to generate the key for symmetric encryption, in order to encrypt other passwords. The idea ...
3
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2answers
634 views

Determine salt length from hash

I am writing a basic Unix password cracker in Python that would work for MD5, SHA-1 and SHA512. I know that the salt in MD5 correspond to the 2 first chars of the encrypted password, and thus I ...
7
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2answers
131 views

Secure way to shorten a hash

If I want to save a hash of a certain number of bits, but my hashing algorithm gives me more bits than I need, then what is the safest way to shorten it? Should I: Just remove the first or last ...
2
votes
1answer
108 views

Is it fine to store single-use beta keys plain-text?

Is it okay to store single-use beta keys in plain-text in the database? I'll be pre-generating and storing about 2M keys. The keys get passed around so that people can sign up with it, rather than let ...
5
votes
1answer
167 views

How to store/encrypt fingerprint?

Storing password is a no brainer : use a password hasher. But.. How do you proceed to store fingerprints securely on your server? Meaning that even if your server and all it's data is stolen, someone ...
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1answer
3k views

Cracking Mysql 5 Hash using Hashcat

I am practicing cracking MYSQL5 hash using hash cat, however, for a reason or another, it finishes the cracking process too fast -within 30 seconds- without giving any results/errors back. I doubted ...
0
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0answers
29 views

Trying to figure out the hashtype of this digest-auth htpasswd file

Simple question for y'all as i'm having some trouble identifying the hash type of this from a http digest file that I have setup for rutorrent on a apache2 server. Here's an example of what it looks ...
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0answers
162 views

Storing Social Security Numbers in a Database

I'm developing an online application that needs the user's social security number. The application won't be processed on the web server so I'll be using an asymmetric key. So a compromised web server ...
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1answer
41 views

How to find an encryption algorithm between two hexadecimal numbers? [closed]

I have several numbers that are generated by a server. They are 16 digits long and are hexadecimal. I have no idea whether or not any salting or hashing techniques were used. Can I find the encryption ...
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3answers
46 views

Hashing Algorithms Costs vs Sleep

I understand most of the concepts behind hashing password but this one still escapes me. I understand that you want the hash to take some time ( a couple milliseconds) so the attacker can't ...
16
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5answers
3k views

The AES Crypt implementation hashes a password 8192 times to generate the key. Is this necessary?

I'm considering encrypting some small files (hundreds of kb apiece) using the AES Crypt reference implementation. Looking at the source, it seems that the encryption key is derived from the IV and the ...
26
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5answers
4k views

Doesn't hashing passwords server side mean a compromised website could leave passwords vulnerable?

So the traffic is encrypted to a website so the password is safe during transmission and also if the website is hacked then the database only contains hashes. But couldn't the hacker create a server ...
1
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2answers
109 views

Double hashing using a relatively new hash and a old, tested one

Note: I am relatively new to cryptography in general, so please point out if I make any misconception here. I heard that you should always use well known crypto/hash functions, that have already been ...
2
votes
4answers
93 views

Is there a security advantage towards hashing a password on the server? [duplicate]

I'm working on an authentification system. Now in this system the user logs in and sends a hashed password to the server. Is this enough or do I have to rehash the password again? So basically is ...
4
votes
1answer
65 views

“MAC function must resist existential forgery under chosen-plaintext attacks”, what does that mean?

While reading about MAC (Message Authentication Code) I have faced this sentence: MAC function must resist existential forgery under chosen-plaintext attacks but I got confused. What does ...
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2answers
69 views

When should a password be hashed? [duplicate]

I develop a Smartphone App and have a little question: When should I hash the user passwords, on the device or upload them in plain text and hash them on the server before stored in the database?
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2answers
503 views

which hashing algorithm is better to use to store a password, sha256 or sha512? [duplicate]

which hashing algorithm is better to use to store a password, sha256 or sha512? I know that sha512 is more secure than sha256 but I was wondering if it has some disadvantages or it is completely ...
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votes
1answer
157 views

Does SHA-512 become suitable to store a password if we use salting and iteration with it?

Today I have read this discussion about SHA-256 and SHA-512 and that we should not use any of them to store a password securely. And I have read here that instead we can use the PBKDF2 hashing ...
3
votes
1answer
65 views

Distributed tokenization for credit card numbers

I have two locations within the same firm that hold credit card numbers. I want to be able to "join" on credit card number to do business analytics after transmitting card number-linked data from one ...
1
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1answer
20 views

Is the method of hardening the creation of a Cryptographically Generated Address (CGA) called hash extension

CGAs are sha1 hashes truncated to a 59 bit value. Along with a 3 bit security parameter they form a IPv6 address (more precisely the interface identifier). from wikipedia: The Sec parameter ...
0
votes
2answers
71 views

Several hashing routines support client side work. Doesn't the hash just become a password equivalent?

Isnt Secure Remote Password Protocol (SRP) pretty much client side hashing? Argon2 the winner of the PHC also allows for client side hashing. How do these systems avoid the plaintext equivalence ...
1
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1answer
82 views

Encrypting data before sending to SaaS tool and decrypting on browser view

I'd like to send data to a SaaS tool, where the data is stored in the cloud. I'll use Google Analytics as an example, but it applies to any similar service. Google Analytics does not allow you to ...
-1
votes
0answers
78 views

Best way to keep encrypted data, which is often decrypted?

I'm starting project for my BSc, where I want to send e-mails with keys (e.g. games on Steam platform, Paysafecard) on Allegro, which is similar to eBay. I will have my own database with users' data ...
1
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1answer
47 views

Virtual Machine Integrity Hash Check

If I used virtualbox to create a snapshot template of a preconfigured linux machine and wanted to ensure that no one has tampered with my snapshot, could I simply keep a comparable hash of the VDI ...
2
votes
1answer
111 views

Reverse engineering of a global hash salt from known plaintext and hash

First of all i'm not asking what is a hash, or something else. I will try to explain what i'm searching clearly: Let's say I have a dump of a database, all the passwords of this database are hashed, ...
0
votes
2answers
74 views

which hash algorithm takes longer time if we compare between md5 or sha256?

Which hash algorithm takes longer time to compute if we compare between md5 and sha256? I do not want to use it for security reasons so I do not care about which one is more secure, I just want to ...
-4
votes
1answer
69 views

How to identify this hash?

I have one hash, I know its value, but not its type. Here is it: 6dfb036bf703d75f9bc8219ba1224d876783fa61 I tried something like php -r "echo sha1('abc');", but it gave me another value, so this ...
7
votes
1answer
304 views

Any problems with scrypt yet?

In the question Do any security experts recommend bcrypt for password storage? Thomas Pornin recommends the hashing function scrypt but saying it is "too new to be recommended on a general basis". ...
1
vote
1answer
51 views

What is the difference between Key Derivation Function and (salted) Hash?

I see in this post that the main difference is that KDF outputs have "certain randomness properties", and I don't understand what does it mean. Suposing that that "certain randomness properties" are ...
2
votes
1answer
59 views

Is it secure to use pbkdf2 for both password hashing and key generation

I'm writing a password manager, right now for each individual site, I already used master password + random salt with PBKDF2 to generate encryption key to encrypt its password (each site has its own ...
2
votes
3answers
142 views

How does a hash which contains algorithm to choose can be secure?

I was thinking about creating my own hash+salt function, something like sha1(password + md5(login)), then I read here (part 4) that creating it's own hash+salt function is a bad idea, because if the ...
7
votes
2answers
1k views

Is it bad practice to ask only for individual characters of a password? [duplicate]

Some financial websites that I use use passwords in a peculiar way. Instead of asking me the whole password string, they only ask me to enter e.g. "3rd, 5th and 8th character of your password", i.e. a ...